Datasets:

Dahoas

/

base_code_review

like 1

<p>I am playing with different ways to do database interaction in PHP, and one of the ideas I have been playing with is connecting to the DB in the constructor and disconnecting in the destructor. This is the code from my <code>Database</code> class.</p> <pre><code>function __construct() { $this-&gt;link = mysql_connect($this-&gt;server.':'.$this-&gt;port, $this-&gt;username); if(!$this-&gt;link) die('Could not connect: '.mysql_error()); if(!mysql_select_db($this-&gt;database, $this-&gt;link)) die('Could not select database: '.mysql_error()); } function __destruct() { if(mysql_close($this-&gt;link)) $this-&gt;link = null; } </code></pre> <p>This works well, my only reservation is that if I need to connect several to hit the database several times it will do multiple connections and disconnects. If I do that a lot I can see, maybe, potential problems. Is this a concern or is there a better way to do this? And is my code even up to snuff in general?</p>

1

<p>I'd like suggestions for optimizing this brute force solution to <a href="http://projecteuler.net/index.php?section=problems&amp;id=1">problem 1</a>. The algorithm currently checks every integer between 3 and 1000. I'd like to cut as many unnecessary calls to <code>isMultiple</code> as possible:</p> <pre><code>''' If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23. Find the sum of all the multiples of 3 or 5 below 1000. ''' end = 1000 def Solution01(): ''' Solved by brute force #OPTIMIZE ''' sum = 0 for i in range(3, end): if isMultiple(i): sum += i print(sum) def isMultiple(i): return (i % 3 == 0) or (i % 5 == 0) </code></pre>

2

<p>Basically, I had written this class a little while ago to ease autoloading of our local libraries. </p> <p>The premise is that everything is split by packages into multiple layers of sub-packages. Classes are named using CamelCasing. So, a class' name is related to its package as follows: <code>PackageSubpackageSubpackageName</code>. Now, each package can have package specific interfaces defined by <code>isPackageName</code> for interfaces, exceptions by <code>PackageNameException</code>, etc. I tried to make it flexible enough for reuse.</p> <pre><code>/** * A class for lazy-loading other classes * * This class enables lazy-loading of php classes. The benefit of this is * three-fold. First, there is a memory benefit, since not all classes are * loaded until they are needed. Second, there is a time benefit, since not all * classes are loaded. Third, it produces cleaner code, since there is no need * to litter files with require_once() calls. * * @category Libraries * @package Libraries * @author Me */ abstract class Loader { /** * @var array An array of class to path mappings */ protected static $classes = array(); /** * @var boolean Has the loader been initialized already */ protected static $initialized = false; /** * @var array An array of auto-search paths */ protected static $namedPaths = array( 'exception', 'interface', 'iterator', ); /** * @var array An array of include paths to search */ protected static $paths = array( PATH_LIBS, ); /** * Tell the auto-loader where to find an un-loaded class * * This can be used to "register" new classes that are unknown to the * system. It can also be used to "overload" a class (redefine it * elsewhere) * * @param string $class The class name to overload * @param string $path The path to the new class * * @throws InvalidArgumentException Upon an Invalid path submission * @return void */ public static function _($class, $path) { $class = strtolower($class); if (!file_exists($path)) { throw new InvalidArgumentException('Invalid Path Specified'); } self::$classes[$class] = $path; } /** * Add a path to the include path list * * This adds a path to the list of paths to search for an included file. * This should not be used to overload classes, since the default include * directory will always be searched first. This can be used to extend * the search path to include new parts of the system * * @param string $path The path to add to the search list * * @throws InvalidArgumentException when an invalid path is specified * @return void */ public static function addPath($path) { if (!is_dir($path)) { throw new InvalidArgumentException('Invalid Include Path Added'); } $path = rtrim($path, DS); if (!in_array($path, self::$paths)) { self::$paths[] = $path; } } /** * Add a path to the auto-search paths (for trailing extensions) * * The path should end with an 's'. Default files should not. * * @param string $path The name of the new auto-search path * * @return void */ public static function addNamedPath($path) { $path = strtolower($path); if (substr($path, -1) == 's') { $path = substr($path, 0, -1); } if (!in_array($path, self::$namedPaths)) { self::$namedPaths[] = $path; } } /** * Initialize and register the autoloader. * * This method will setup the autoloader. This should only be called once. * * @return void */ public static function initialize() { if (!self::$initialized) { self::$initialized = true; spl_autoload_register(array('Loader', 'load')); } } /** * The actual auto-loading function. * * This is automatically called by PHP whenever a class name is used that * doesn't exist yet. There should be no need to manually call this method. * * @param string $class The class name to load * * @return void */ public static function load($class) { $className = strtolower($class); if (isset(self::$classes[$className])) { $file = self::$classes[$className]; } else { $file = self::findFile($class); } if (file_exists($file)) { include_once $file; } } /** * Find the file to include based upon its name * * This splits the class name by uppercase letter, and then rejoins them * to attain the file system path. So FooBarBaz will be turned into * foo/bar/baz. It then searches the include paths for that chain. If baz * is a directory, it searches that directory for a file called baz.php. * Otherwise, it looks for baz.php under the bar directory. * * @param string $class The name of the class to find * * @return string The path to the file defining that class */ protected static function findFile($class) { $regex = '#([A-Z]{1}[a-z0-9_]+)#'; $options = PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE; $parts = preg_split($regex, $class, null, $options); $subpath = ''; $file = strtolower(end($parts)); $test = strtolower(reset($parts)); if ($test == 'is') { array_shift($parts); return self::findNamedFile($class, $parts, 'interface'); } foreach ($parts as $part) { $subpath .= DS . strtolower($part); } foreach (self::$paths as $path) { $newpath = $path . $subpath; if (is_file($newpath . '.php')) { return $newpath . '.php'; } elseif (is_file($newpath . DS . $file . '.php')) { return $newpath . DS . $file . '.php'; } } if (in_array($file, self::$namedPaths)) { //Get rid of the trailing part array_pop($parts); return self::findNamedFile($class, $parts, $file); } return ''; } /** * Find a file for named directories (interfaces, exceptions, iterators, etc) * * @param string $class The class name of the exception to find * @param array $parts The parts of the class name pre-split * @param string $name The name of the named directory to search in * * @return string The found path, or '' if not found */ protected static function findNamedFile($class, array $parts, $name) { if (empty($parts)) { return ''; } $name = strtolower($name); //Add a trailing s, since individual files are not plural $filename = $name; $name .= 's'; //Try the global path first $subpath = DS . $name . DS . strtolower(implode('', $parts)) . '.php'; foreach (self::$paths as $path) { $newpath = $path . $subpath; if (is_file($newpath)) { return $newpath; } } //Try to build a full sub path for package specific named files $package = array_shift($parts); $subpath = DS . strtolower($package) . DS . $name . DS; if (!empty($parts)) { $subpath .= strtolower(implode('', $parts)) . '.php'; } else { $subpath .= $filename . '.php'; } foreach (self::$paths as $path) { $newpath = $path . $subpath; if (is_file($newpath)) { return $newpath; } } return ''; } } </code></pre> <p>It's also fully unit tested.</p> <p>What are your thoughts? Is it over-complex?</p>

4

<p>I started programming with Java and C++, so I'm used to having a 'main' function that calls other functions that do the actual work. At university I was always told that doing actual computation in the main function is bad practice. I'm currently playing around with Python, and I have trouble figuring out how to write a nice 'main' function, especially since I'm doing small stuff that doesn't need separate classes.</p> <p>What do you think about the following code? Is the main function necessary, or would you just write everything without functions? Is there a general consent on this in the Python world?</p> <pre><code># Finds sum of all multiples of 3 and 5 from 0 to 999 def find_multiples(): global numbers for i in range(0,1000): if i%3==0 or i%5==0: numbers.append(i); numbers = [] if __name__ == '__main__': find_multiples() print sum(numbers) </code></pre>

7

<p>I have a method that has a lot of loops:</p> <pre><code>private void update(double depth) { Console.WriteLine("update with level " + depth); this.Dispatcher.Invoke(System.Windows.Threading.DispatcherPriority.Normal, new Action(delegate() { List&lt;Grid&gt; grids = new List&lt;Grid&gt;(); Dependencies.Children.Clear(); Grid g = new Grid(); //Canvas.SetZIndex(g, 100); g.Width = 50; g.Height = 50; g.Tag = focus; Ellipse e = new Ellipse(); e.Width = 50; e.Height = 50; e.Fill = Brushes.Red; if (depth == 1) { Canvas.SetTop(g, 163); } else if (depth == 2) { Canvas.SetTop(g, 108); } else if (depth == 3) { Canvas.SetTop(g, 81); } else if (depth == 4) { Canvas.SetTop(g, 65); } else if (depth == 5) { Canvas.SetTop(g, 54); } else if (depth == 6) { Canvas.SetTop(g, 46); } Canvas.SetLeft(g, 500); g.Children.Add(e); Viewbox box = new Viewbox(); box.Width = e.Width; box.Height = e.Height; TextBox txt = new TextBox(); txt.Text = focus.getName(); box.Child = txt; txt.Background = Brushes.Transparent; txt.BorderBrush = Brushes.Transparent; g.Children.Add(box); grids.Add(g); List&lt;SourceFile&gt; list = new List&lt;SourceFile&gt;(); list = focus.getInvocations(); int counter = 1; foreach (SourceFile sf in list) { Grid g1 = new Grid(); //Canvas.SetZIndex(g, 101); g1.Width = 50; g1.Height = 50; g1.Tag = sf; Ellipse e1 = new Ellipse(); //Dependencies.Children.Add(e1); sf.setGrid(g1); e1.Width = 50; e1.Height = 50; e1.Fill = Brushes.Red; g1.Children.Add(e1); if (depth == 1) { Canvas.SetTop(g1, 488); } else if (depth == 2) { Canvas.SetTop(g1, 324); } else if (depth == 3) { Canvas.SetTop(g1, 244); } else if (depth == 4) { Canvas.SetTop(g1, 195); } else if (depth == 5) { Canvas.SetTop(g1, 163); } else if (depth == 6) { Canvas.SetTop(g1, 139); } Canvas.SetLeft(g1, counter * (1000 / (list.Count + 1) )); Viewbox box1 = new Viewbox(); box1.Width = g1.Width; box1.Height = g1.Height; TextBox txt1 = new TextBox(); txt1.Text = sf.getName(); txt1.Background = Brushes.Transparent; txt1.BorderBrush = Brushes.Transparent; box1.Child = txt1; g1.Children.Add(box1); Line l = new Line(); //Canvas.SetZIndex(l, 1); l.Stroke = Brushes.Green; l.StrokeThickness = 10; Binding x1 = new Binding(); x1.Path = new PropertyPath(Canvas.LeftProperty); x1.Converter = new MyConverter(); x1.ConverterParameter = g; Binding y1 = new Binding(); y1.Path = new PropertyPath(Canvas.TopProperty); y1.Converter = new MyConverter(); y1.ConverterParameter = g; Binding x2 = new Binding(); x2.Path = new PropertyPath(Canvas.LeftProperty); x2.Converter = new MyConverter(); x2.ConverterParameter = g1; Binding y2 = new Binding(); y2.Path = new PropertyPath(Canvas.TopProperty); y2.Converter = new MyConverter(); y2.ConverterParameter = g1; x1.Source = y1.Source = g; x2.Source = y2.Source = g1; l.SetBinding(Line.X1Property, x1); l.SetBinding(Line.Y1Property, y1); l.SetBinding(Line.X2Property, x2); l.SetBinding(Line.Y2Property, y2); Dependencies.Children.Add(l); l.Tag = new Call(focus, sf); Contacts.AddPreviewContactDownHandler(l, OnLineDown); counter++; grids.Add(g1); SizeChangedEventHandler act = (Object s, SizeChangedEventArgs args) =&gt; { BindingOperations.GetBindingExpressionBase(l, Line.X1Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.Y1Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.X2Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.Y2Property).UpdateTarget(); }; g.SizeChanged += act; g1.SizeChanged += act; } int counter2 = 1; if (depth &gt;= 2) { int invocCount = 0; foreach (SourceFile s in list) { foreach (SourceFile source in s.getInvocations()) { invocCount = invocCount + s.getInvocations().Count; } } Console.WriteLine(invocCount); foreach (SourceFile s in list) { foreach (SourceFile source in s.getInvocations()) { Console.WriteLine("`Found invocation of " + s.getName() + ": " + source.getName()); Grid g1 = new Grid(); g1.Width = 50; g1.Height = 50; Ellipse e1 = new Ellipse(); // Canvas.SetZIndex(g1, 102); grids.Add(g1); e1.Width = 50; e1.Height = 50; e1.Fill = Brushes.Red; source.setGrid(g1); g1.Tag = source; g1.Children.Add(e1); if (depth == 2) { Canvas.SetTop(g1, 540); } else if (depth == 3) { Canvas.SetTop(g1, 406); } else if (depth == 4) { Canvas.SetTop(g1, 325); } else if (depth == 5) { Canvas.SetTop(g1, 271); } else if (depth == 6) { Canvas.SetTop(g1, 232); } Canvas.SetLeft(g1, counter2 * (1000 / (invocCount + 1))); Viewbox box1 = new Viewbox(); box1.Width = g1.Width; box1.Height = g1.Height; TextBox txt1 = new TextBox(); txt1.Text = source.getName(); txt1.Background = Brushes.Transparent; txt1.BorderBrush = Brushes.Transparent; box1.Child = txt1; g1.Children.Add(box1); Line l = new Line(); //Canvas.SetZIndex(l, 2); l.Stroke = Brushes.Green; l.StrokeThickness = 10; Binding x1 = new Binding(); x1.Path = new PropertyPath(Canvas.LeftProperty); x1.Converter = new MyConverter(); x1.ConverterParameter = s.getGrid(); Binding y1 = new Binding(); y1.Path = new PropertyPath(Canvas.TopProperty); y1.Converter = new MyConverter(); y1.ConverterParameter = s.getGrid(); Binding x2 = new Binding(); x2.Path = new PropertyPath(Canvas.LeftProperty); x2.Converter = new MyConverter(); x2.ConverterParameter = g1; Binding y2 = new Binding(); y2.Path = new PropertyPath(Canvas.TopProperty); y2.Converter = new MyConverter(); y2.ConverterParameter = g1; x1.Source = y1.Source = findGrid(grids, s, source); x2.Source = y2.Source = g1; l.SetBinding(Line.X1Property, x1); l.SetBinding(Line.Y1Property, y1); l.SetBinding(Line.X2Property, x2); l.SetBinding(Line.Y2Property, y2); Dependencies.Children.Add(l); l.Tag = new Call(s, source); Contacts.AddPreviewContactDownHandler(l, OnLineDown); counter2++; SizeChangedEventHandler act = (Object o, SizeChangedEventArgs args) =&gt; { BindingOperations.GetBindingExpressionBase(l, Line.X1Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.Y1Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.X2Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.Y2Property).UpdateTarget(); }; source.getGrid().SizeChanged += act; g1.SizeChanged += act; } } } int counter3 = 1; if (depth &gt;= 3) { int invocCount = 0; foreach (SourceFile s in list) { foreach (SourceFile source in s.getInvocations()) { foreach (SourceFile s1 in source.getInvocations()) { invocCount = invocCount + source.getInvocations().Count; } } } foreach (SourceFile s in list) { foreach (SourceFile source in s.getInvocations()) { foreach (SourceFile s1 in source.getInvocations()) { Grid g1 = new Grid(); grids.Add(g1); g1.Width = 50; g1.Height = 50; g1.Tag = s1; Ellipse e1 = new Ellipse(); e1.Width = 50; e1.Height = 50; e1.Fill = Brushes.Red; s1.setGrid(g1); g1.Children.Add(e1); if (depth == 3) { Canvas.SetTop(g1, 569); } else if (depth == 4) { Canvas.SetTop(g1, 455); } else if (depth == 5) { Canvas.SetTop(g1, 379); } else if (depth == 6) { Canvas.SetTop(g1, 325); } Canvas.SetLeft(g1, counter3 * (1000 / (invocCount + 1))); Viewbox box1 = new Viewbox(); box1.Width = g1.Width; box1.Height = g1.Height; TextBox txt1 = new TextBox(); txt1.Background = Brushes.Transparent; txt1.BorderBrush = Brushes.Transparent; txt1.Text = s1.getName(); box1.Child = txt1; g1.Children.Add(box1); Line l = new Line(); //Canvas.SetZIndex(l, 2); l.Stroke = Brushes.Green; l.StrokeThickness = 10; Binding x1 = new Binding(); x1.Path = new PropertyPath(Canvas.LeftProperty); x1.Converter = new MyConverter(); x1.ConverterParameter = source.getGrid(); Binding y1 = new Binding(); y1.Path = new PropertyPath(Canvas.TopProperty); y1.Converter = new MyConverter(); y1.ConverterParameter = source.getGrid(); Binding x2 = new Binding(); x2.Path = new PropertyPath(Canvas.LeftProperty); x2.Converter = new MyConverter(); x2.ConverterParameter = g1; Binding y2 = new Binding(); y2.Path = new PropertyPath(Canvas.TopProperty); y2.Converter = new MyConverter(); y2.ConverterParameter = g1; x1.Source = y1.Source = findGrid(grids, source, s1); x2.Source = y2.Source = g1; l.SetBinding(Line.X1Property, x1); l.SetBinding(Line.Y1Property, y1); l.SetBinding(Line.X2Property, x2); l.SetBinding(Line.Y2Property, y2); Dependencies.Children.Add(l); l.Tag = new Call(source, s1); Contacts.AddPreviewContactDownHandler(l, OnLineDown); counter3++; SizeChangedEventHandler act = (Object o, SizeChangedEventArgs args) =&gt; { BindingOperations.GetBindingExpressionBase(l, Line.X1Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.Y1Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.X2Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.Y2Property).UpdateTarget(); }; s1.getGrid().SizeChanged += act; g1.SizeChanged += act; } } } } int counter4 = 1; if (depth &gt;= 4) { int invoCount = 0; foreach (SourceFile s in list) { foreach (SourceFile source in s.getInvocations()) { foreach (SourceFile s1 in source.getInvocations()) { foreach (SourceFile s2 in s1.getInvocations()) { invoCount = invoCount + s1.getInvocations().Count; } } } } foreach (SourceFile s in list) { foreach (SourceFile source in s.getInvocations()) { foreach (SourceFile s1 in source.getInvocations()) { foreach (SourceFile s2 in s1.getInvocations()) { Grid g1 = new Grid(); grids.Add(g1); g1.Width = 50; g1.Height = 50; g1.Tag = s2; Ellipse e1 = new Ellipse(); e1.Width = 50; e1.Height = 50; e1.Fill = Brushes.Red; s2.setGrid(g1); g1.Children.Add(e1); if (depth == 4) { Canvas.SetTop(g1, 585); } else if (depth == 5) { Canvas.SetTop(g1, 488); } else if (depth == 6) { Canvas.SetTop(g1, 418); } Canvas.SetLeft(g1, counter4 * (1000 / (invoCount + 1))); Viewbox box1 = new Viewbox(); box1.Width = g1.Width; box1.Height = g1.Height; TextBox txt1 = new TextBox(); txt1.Background = Brushes.Transparent; txt1.BorderBrush = Brushes.Transparent; txt1.Text = s2.getName(); box1.Child = txt1; g1.Children.Add(box1); Line l = new Line(); //Canvas.SetZIndex(l, 2); l.Stroke = Brushes.Green; l.StrokeThickness = 10; Binding x1 = new Binding(); x1.Path = new PropertyPath(Canvas.LeftProperty); x1.Converter = new MyConverter(); x1.ConverterParameter = s1.getGrid(); Binding y1 = new Binding(); y1.Path = new PropertyPath(Canvas.TopProperty); y1.Converter = new MyConverter(); y1.ConverterParameter = s1.getGrid(); Binding x2 = new Binding(); x2.Path = new PropertyPath(Canvas.LeftProperty); x2.Converter = new MyConverter(); x2.ConverterParameter = g1; Binding y2 = new Binding(); y2.Path = new PropertyPath(Canvas.TopProperty); y2.Converter = new MyConverter(); y2.ConverterParameter = g1; x1.Source = y1.Source = findGrid(grids, s1, s2); x2.Source = y2.Source = g1; l.SetBinding(Line.X1Property, x1); l.SetBinding(Line.Y1Property, y1); l.SetBinding(Line.X2Property, x2); l.SetBinding(Line.Y2Property, y2); Dependencies.Children.Add(l); l.Tag = new Call(s1, s2); Contacts.AddPreviewContactDownHandler(l, OnLineDown); counter4++; SizeChangedEventHandler act = (Object o, SizeChangedEventArgs args) =&gt; { BindingOperations.GetBindingExpressionBase(l, Line.X1Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.Y1Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.X2Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.Y2Property).UpdateTarget(); }; s2.getGrid().SizeChanged += act; g1.SizeChanged += act; } } } } } int counter5 = 1; if (depth &gt;= 5) { int invoCount = 0; foreach (SourceFile s in list) { foreach (SourceFile source in s.getInvocations()) { foreach (SourceFile s1 in source.getInvocations()) { foreach (SourceFile s2 in s1.getInvocations()) { foreach (SourceFile s3 in s2.getInvocations()) { invoCount = invoCount + s2.getInvocations().Count; } } } } } foreach (SourceFile s in list) { foreach (SourceFile source in s.getInvocations()) { foreach (SourceFile s1 in source.getInvocations()) { foreach (SourceFile s2 in s1.getInvocations()) { foreach (SourceFile s3 in s2.getInvocations()) { Grid g1 = new Grid(); g1.Width = 50; g1.Height = 50; grids.Add(g1); g1.Tag = s3; Ellipse e1 = new Ellipse(); //Dependencies.Children.Add(e1); e1.Width = 50; e1.Height = 50; e1.Fill = Brushes.Red; s3.setGrid(g1); g1.Children.Add(e1); if (depth == 5) { Canvas.SetTop(g1, 596); } else if (depth == 6) { Canvas.SetTop(g1, 511); } Canvas.SetLeft(g1, counter5 * (1000 / (invoCount + 1))); Viewbox box1 = new Viewbox(); box1.Width = g1.Width; box1.Height = g1.Height; TextBox txt1 = new TextBox(); txt1.Background = Brushes.Transparent; txt1.BorderBrush = Brushes.Transparent; txt1.Text = s3.getName(); box1.Child = txt1; g1.Children.Add(box1); Line l = new Line(); //Canvas.SetZIndex(l, 2); l.Stroke = Brushes.Green; l.StrokeThickness = 10; Binding x1 = new Binding(); x1.Path = new PropertyPath(Canvas.LeftProperty); x1.Converter = new MyConverter(); x1.ConverterParameter = s2.getGrid(); Binding y1 = new Binding(); y1.Path = new PropertyPath(Canvas.TopProperty); y1.Converter = new MyConverter(); y1.ConverterParameter = s2.getGrid(); Binding x2 = new Binding(); x2.Path = new PropertyPath(Canvas.LeftProperty); x2.Converter = new MyConverter(); x2.ConverterParameter = g1; Binding y2 = new Binding(); y2.Path = new PropertyPath(Canvas.TopProperty); y2.Converter = new MyConverter(); y2.ConverterParameter = g1; x1.Source = y1.Source = findGrid(grids, s2, s3); x2.Source = y2.Source = g1; l.SetBinding(Line.X1Property, x1); l.SetBinding(Line.Y1Property, y1); l.SetBinding(Line.X2Property, x2); l.SetBinding(Line.Y2Property, y2); l.Tag = new Call(s2, s3); Contacts.AddPreviewContactDownHandler(l, OnLineDown); Dependencies.Children.Add(l); counter5++; SizeChangedEventHandler act = (Object o, SizeChangedEventArgs args) =&gt; { BindingOperations.GetBindingExpressionBase(l, Line.X1Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.Y1Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.X2Property).UpdateTarget(); BindingOperations.GetBindingExpressionBase(l, Line.Y2Property).UpdateTarget(); }; s3.getGrid().SizeChanged += act; g1.SizeChanged += act; } } } } } } foreach (Grid grid in grids) { Dependencies.Children.Add(grid); Contacts.AddPreviewContactDownHandler(grid, DownOnSourceFile); } } )); } </code></pre> <p>Is there any easy way to improve that? And to make it working not only for 6 steps but also for n steps?</p>

9

<p>I use <a href="https://codeigniter.com/" rel="nofollow noreferrer">CodeIgniter</a> at work, and one of our model files had a lot of subqueries in it. I originally had to manually write each subquery, and wondered if I could use active records instead.</p> <p>So, to make my life easier, I made a subquery library for CodeIgniter.</p> <p>I put it on the <a href="https://github.com/bcit-ci/CodeIgniter/wiki/Subqueries" rel="nofollow noreferrer">CodeIgniter Wiki</a>, but I never really had any one look over it. So, can you tell me if there is anything I should improve in this, or anything I really shouldn't be doing?</p> <p>P.S. Feel free to use this if you wish.</p> <p>P.P.S. <code>join_range</code> is a helper method for use with the answer to <a href="https://stackoverflow.com/questions/4155873/mysql-find-in-set-vs-in">this question</a>.</p> <p>P.P.P.S. The latest version can be found <a href="https://github.com/NTICompass/CodeIgniter-Subqueries" rel="nofollow noreferrer">here</a>.</p> <pre><code>class Subquery{ var $CI; var $db; var $statement; var $join_type; var $join_on; function __construct(){ $this-&gt;CI =&amp; get_instance(); $this-&gt;db = array(); $this-&gt;statement = array(); $this-&gt;join_type = array(); $this-&gt;join_on = array(); } /** * start_subquery - Creates a new database object to be used for the subquery * * @param $statement - SQL statement to put subquery into (select, from, join, etc.) * @param $join_type - JOIN type (only for join statements) * @param $join_on - JOIN ON clause (only for join statements) * * @return A new database object to use for subqueries */ function start_subquery($statement, $join_type='', $join_on=1){ $db = $this-&gt;CI-&gt;load-&gt;database('', true); $this-&gt;db[] = $db; $this-&gt;statement[] = $statement; if(strtolower($statement) == 'join'){ $this-&gt;join_type[] = $join_type; $this-&gt;join_on[] = $join_on; } return $db; } /** * end_subquery - Closes the database object and writes the subquery * * @param $alias - Alias to use in query * * @return none */ function end_subquery($alias=''){ $db = array_pop($this-&gt;db); $sql = &quot;({$db-&gt;_compile_select()})&quot;; $alias = $alias!='' ? &quot;AS $alias&quot; : $alias; $statement = array_pop($this-&gt;statement); $database = (count($this-&gt;db) == 0) ? $this-&gt;CI-&gt;db: $this-&gt;db[count($this-&gt;db)-1]; if(strtolower($statement) == 'join'){ $join_type = array_pop($this-&gt;join_type); $join_on = array_pop($this-&gt;join_on); $database-&gt;$statement(&quot;$sql $alias&quot;, $join_on, $join_type); } else{ $database-&gt;$statement(&quot;$sql $alias&quot;); } } /** * join_range - Helper function to CROSS JOIN a list of numbers * * @param $start - Range start * @param $end - Range end * @param $alias - Alias for number list * @param $table_name - JOINed tables need an alias(Optional) */ function join_range($start, $end, $alias, $table_name='q'){ $range = array(); foreach(range($start, $end) AS $r){ $range[] = &quot;SELECT $r AS $alias&quot;; } $range[0] = substr($range[0], 7); $range = implode(' UNION ALL ', $range); $sub = $this-&gt;start_subquery('join', 'inner'); $sub-&gt;select($range, false); $this-&gt;end_subquery($table_name); } } </code></pre> <p><strong>Example Usage</strong></p> <p>This query:</p> <pre><code>SELECT `word`, (SELECT `number` FROM (`numbers`) WHERE `numberID` = 2) AS number FROM (`words`) WHERE `wordID` = 3 </code></pre> <p>would become:</p> <pre><code>$this-&gt;db-&gt;select('word')-&gt;from('words')-&gt;where('wordID', 3); $sub = $this-&gt;subquery-&gt;start_subquery('select'); $sub-&gt;select('number')-&gt;from('numbers')-&gt;where('numberID', 2); $this-&gt;subquery-&gt;end_subquery('number'); </code></pre>

12

<p>So I've had a problem where I need to compare data in 2 different tables on two different servers. Now, I know MySQL supports <code>CHECKSUM TABLES</code>, but from my testing and understanding, it's not reliable across server instances and versions. </p> <p>So I created this query:</p> <pre><code>$part = '@CRC := MD5(CONCAT_WS(\'#\', COALESCE(`'. implode('`, "#NULL#"), COALESCE(`', $this-&gt;_columns). '`, "#NULL#")))'; $sql1 = "SELECT COUNT(*) AS cnt, SUM(CONV(SUBSTRING({$part}, 1, 4), 16, 10)) as a1, SUM(CONV(SUBSTRING(@CRC, 5, 4), 16, 10)) as a2, SUM(CONV(SUBSTRING(@CRC, 9, 4), 16, 10)) as a3, SUM(CONV(SUBSTRING(@CRC, 13, 4), 16, 10)) as a4, SUM(CONV(SUBSTRING(@CRC, 17, 4), 16, 10)) as a5, SUM(CONV(SUBSTRING(@CRC, 21, 4), 16, 10)) as a6, SUM(CONV(SUBSTRING(@CRC, 25, 4), 16, 10)) as a7, SUM(CONV(SUBSTRING(@CRC, 29, 4), 16, 10)) as a8 FROM `dbname`.`tablename` WHERE `id` &gt;= $min AND `id` &lt;= $max "; </code></pre> <p>So basically, it's concatenating each row together (all the columns of each row more specifically) and then MD5ing them. Then it walks 4 hexbits at a time through that MD5 and sums them across all rows (4 hexbits to allow me to do huge tables without needing to worry about overflowing). Then, I just compare the result of this query on both tables to see if everything is the same.</p> <p>By using this binary search, I am able to rather quickly narrow down where the changes are so that I can port them.</p> <p>It's actually reasonably efficient, so I'm not too concerned about that. What I am concerned about is if this is even necessary. It's screaming to me "You're doing it wrong", but I can't figure out any cleaner method around it...</p> <p>What are your thoughts?</p>

16

<p>A while back, I reverse-engineered a checksum algorithm from an <a href="http://en.wikipedia.org/wiki/Massively_multiplayer_online_game" rel="noreferrer">MMO</a> used to check the validity of an item that's linked to chat (similar to <a href="http://en.wikipedia.org/wiki/World_of_Warcraft" rel="noreferrer"><em>WoW</em></a>). The idea is that if the checksum is invalid then the game client would ignore the link when clicked. Otherwise clicking on the item link in in-game chat would display the stat and attrib for that item.</p> <pre><code>ushort16 CreateChecksum(const string &amp;itemlink) { stringstream parseitemlink(itemlink); uint32 hexform[ITEMLINKGROUPCOUNT] = {0}; uint32 hexsum = 0; //Parse itemLink string into hexform array for (int i = 0; i &lt; ITEMLINKGROUPCOUNT; ++i) parseitemlink &gt;&gt; hex &gt;&gt; hexform[i]; //sum all the itemlink group together for (int i = 0; i &lt; ITEMLINKGROUPCOUNT; ++i) hexsum += hexform[i]; for (int i = 0; i &lt; ITEMLINKGROUPCOUNT; ++i) { uint32 ebx = hexform[i], edi = ebx * i; //if loop iteration is odd store MSB 2-bytes. //Otherwise, store working hexgroup as is untouched if (i &amp; 0x01) ebx = hexform[i] &gt;&gt; 16; // aka same as dividing hexform[i] by 65,536 // (hexform[i] / 65,536) + (hexform[i] * i) + hexsum -- for odd groups // hexform[i] + (hexform[i] * i) + hexsum -- for even groups ebx += edi + hexsum; hexsum = ebx ^ hexform[i]; } for (int i = 0; i &lt; ITEMLINKGROUPCOUNT; ++i) { // the more familiar high-level form would be // hexform[i]^2 + hexform[i] * hexsum uint32 ecx = (hexform[i] + 1) * hexsum, eax = ecx * hexform[i]; eax &gt;&gt;= 16; eax += ecx; hexsum = eax ^ hexform[i]; } //return the lower 2-bytes of hexsum //as the final checksum return hexsum &amp; 0xFFFF; }//CreateChecksum </code></pre> <p>The format of the <code>itemlink</code> is comprised of a group of hexadecimal separated with a space in string format. It's passed into <code>main()</code> as an argument when the program is run.</p> <p>Here's what an <code>itemlink</code>'s hex string might look like:</p> <blockquote> <pre><code>const string EXAMPLELINK = "36c6a 0 3f000a54 d0f1 0 0 0 0 0 0 20d0"; </code></pre> </blockquote> <p>Are there any code smells or readability issues in this code segment? Can any part(s) of it be improved?</p>

22

<p>I'm generating CSV strings for various 3rd party utilities and this section of code gets repeated in many classes. Is there a better way to generate this string?</p> <pre><code>public override string CsvString() { return ( string.Format("\u0022{0}\u0022,\u0022{1}\u0022,\u0022{2}\u0022,\u0022{3}\u0022,\u0022{4}\u0022,\u0022{5}\u0022,\u0022{6}\u0022,\u0022{7}\u0022,\u0022{8}\u0022,\u0022{9}\u0022,\u0022{10}\u0022,\u0022{11}\u0022,\u0022{12}\u0022,\u0022{13}\u0022", this.BlockType, // 1, A_NAME this.Tag, // 2, A_TAG this.Description, // 3, A_DESC this.InitialScan, // 4, A_ISCAN this.AutoManual, // 5, A_SCAN this.ScanTime, // 6, A_SCANT this.IoDevice, // 7, A_IODV this.IoAddress, // 8, A_IOAD this.InitialAmStatus, // 9, A_IAM this.AlarmPriority, // 10, A_PRI this.AlarmEnable, // 11, A_ENAB this.EnableOutput, // 12, A_EOUT this.HistDescription, // 13, A_HIST_DESC this.SecurityArea1 // 14, A_SECURITYAREA1 )); } </code></pre>

36

<p>A few functions to let me manage TAGS files more easily. Typically, my projects contain at least one sub-folder. I got sick of manually updating, so I wrote this to help me update a single TAGS file per project (always in the projects' root directory).</p> <p>Please share your thoughts (aside from "Why are you using Emacs?", you're not likely to change my mind).</p> <p>One thing I've noticed that could trip me up is that it only tags files of one language (and if I had a project that had both Haskell and JS code, for example, I could tag one or the other). I would particularly appreciate advice on better ways to write find-parent-tags than just building each path from available sub-strings.</p> <pre><code>(defun create-tag-table () "This will recursively tag all files of a given type starting with the current buffers' directory. It overwrites the old TAGS file, if one exists. Haskell files assume you've installed `hasktags`." (interactive) (let ((file-type (get-taggable-extension)) (cur-dir default-directory) (tags-file (find-parent-tags default-directory))) (if (equalp file-type "hs") (shell-command "hasktags --ignore-close-implementation --etags `find . -type f -name \"*.*hs\"`") (shell-command (concat "find -name \"*." file-type "\" -print | etags -"))))) (defun find-parent-tags (dir) "Traverses the directory tree up to /home/[user]/ or / whichever comes first. Returns either nil or the directory containing the first TAGS file it finds." (interactive (list default-directory)) (find-parent-tags-rec (build-tag-paths dir))) (defun find-parent-tags-rec (list-of-filepath) (cond ((null list-of-filepath) nil) ((file-exists-p (car list-of-filepath)) (car list-of-filepath)) (t (find-parent-tags-rec (cdr list-of-filepath))))) (defun build-tag-paths (dir-string) (build-tag-paths-rec (remove-if #'empty-string? (split-string dir-string "/")) (list "/"))) (defun build-tag-paths-rec (steps acc) (if (null steps) (mapcar (lambda (p) (concat p "TAGS")) acc) (build-tag-paths-rec (cdr steps) (cons (concat (car acc) (car steps) "/") acc)))) (defun get-taggable-extension () "Either returns the current file's extension (if it's appropriate) or asks the user to pick one with completion" (let ((b-name (buffer-file-name (current-buffer))) (valid-exts (list "lisp" "py" "c" "hs" "rb" "ss" "scm" "js" "erl" "el"))) (string-match "\\.\\(.*?\\)$" b-name) (let ((current-filetype (match-string 1 b-name))) (if (member current-filetype valid-exts) current-filetype (completing-read "File type: " valid-exts nil 'confirm))))) (defun empty-string? (s) (equalp s "")) (provide 'tagariffic) </code></pre>

45

<p>This shows a test case for an old caching library that I use for a project. It features simple save/load/delete functions (sadly static calls) but what I want to focus on is the test code written for this class.</p> <p>In my opinion the unit tests for a class should show how all functions in the class work and what to <em>expect</em> from that class.</p> <p>Recently we got this great change to show off code, so I'd like to ask you if you can read that test code, understand what the class might do and how you would improve upon it.</p> <pre><code>&lt;?php class DatenCacheTest extends PHPUnit_Framework_TestCase { function testNothingFound() { $this-&gt;assertSame(false, DatenCache::load("testNotHereCache")); } function testSaveLoadSimple() { $sDatenSimple = "testStringSaveLoadSimple"; $sDatenSimpleParam = "testStringParam"; $sDatenSimpleParam2 = "testStringParam2"; $sDatenSimpleParam3 = ""; $sDatenSimpleParam4 = 0; $this-&gt;assertSame(true, DatenCache::save("testCacheSimple", false, $sDatenSimple)); $this-&gt;assertSame($sDatenSimple, DatenCache::load("testCacheSimple", false)); $this-&gt;assertSame(true, DatenCache::save("testCacheLinearParam", "string", $sDatenSimpleParam)); $this-&gt;assertSame($sDatenSimpleParam, DatenCache::load("testCacheLinearParam", "string")); $this-&gt;assertSame(true, DatenCache::save("testCacheLinearParam", 5, $sDatenSimpleParam2)); $this-&gt;assertSame($sDatenSimpleParam2, DatenCache::load("testCacheLinearParam", 5)); $this-&gt;assertSame(true, DatenCache::save("testCacheBoundStringParam", false, $sDatenSimpleParam3)); $this-&gt;assertSame($sDatenSimpleParam3, DatenCache::load("testCacheBoundStringParam", false)); $this-&gt;assertSame(true, DatenCache::save("testCacheBoundIntParam", false, $sDatenSimpleParam4)); $this-&gt;assertSame($sDatenSimpleParam4, DatenCache::load("testCacheBoundIntParam", false)); $oObj = new stdClass(); $oObj-&gt;bob = 2; $this-&gt;assertSame(true, DatenCache::save("testCacheBoundObjParam", $oObj, "zwei")); $this-&gt;assertSame("zwei", DatenCache::load("testCacheBoundObjParam", $oObj)); } function testSaveLoadArray() { $aDaten = array("da" =&gt; "ten", array("ten" =&gt; "da"), "Striche" =&gt; "' \";s:5:", "h''uh" =&gt; "mep", "\\mep\\" =&gt; "^^", "Zeilenumbruch" =&gt; "\n", "Zeug" =&gt; "::}}{:", "'" =&gt; '"', '"' =&gt; "'"); $this-&gt;assertSame(true, DatenCache::save("testCacheArray", false, $aDaten)); $this-&gt;assertSame($aDaten, DatenCache::load("testCacheArray", false)); } function testSaveLoadExpired() { $this-&gt;assertSame(true, DatenCache::save("testCacheExpired", false, "testStringLoadExpired", "-1 seconds")); $this-&gt;assertSame(false, DatenCache::load("testCacheExpired", false)); } function testSaveLoadObject() { $oObj = new stdClass(); $oObj-&gt;bob = 2; $this-&gt;assertSame(true, DatenCache::save("testCacheBoundIntParam", false, $oObj)); $oNewObj = DatenCache::load("testCacheBoundIntParam", false); $this-&gt;assertEquals($oObj, $oNewObj); $this-&gt;assertSame($oObj-&gt;bob, $oNewObj-&gt;bob); } function testSaveLoadComplexParam() { $aKonfigEins = array(DatenCache::ANLAGEN_ID() =&gt; 1, DatenCache::SESSION_ID() =&gt; "id1"); $aKonfigZwei = array(DatenCache::ANLAGEN_ID() =&gt; 1, DatenCache::SESSION_ID() =&gt; "id2"); $aKonfigDrei = array(DatenCache::ANLAGEN_ID() =&gt; 1, DatenCache::SESSION_ID() =&gt; "id3"); $aKonfigVier = array(DatenCache::ANLAGEN_ID() =&gt; 1); $aKonfigFuenf = array(DatenCache::SESSION_ID() =&gt; "id3"); $aKonfigSechs = array(DatenCache::ANLAGEN_ID() =&gt; 1, DatenCache::SESSION_ID() =&gt; "id3", DatenCache::PERSON_ID() =&gt; 1); $this-&gt;assertSame(true, DatenCache::save("testCacheComplexParam", $aKonfigEins, "v1")); $this-&gt;assertSame("v1", DatenCache::load("testCacheComplexParam", $aKonfigEins)); $this-&gt;assertSame(true, DatenCache::save("testCacheComplexParam", $aKonfigZwei, "v2")); $this-&gt;assertSame("v2", DatenCache::load("testCacheComplexParam", $aKonfigZwei)); $this-&gt;assertSame(false, DatenCache::load("testCacheComplexParam", $aKonfigDrei)); $this-&gt;assertSame(false, DatenCache::load("testCacheComplexParam", $aKonfigVier)); $this-&gt;assertSame(false, DatenCache::load("testCacheComplexParam", $aKonfigFuenf)); $this-&gt;assertSame(false, DatenCache::load("testCacheComplexParam", $aKonfigSechs)); } function testInvalidate() { $this-&gt;assertSame(true, DatenCache::save("testCacheSimple", false, "testStringInvalidate")); DatenCache::invalidate("testCacheSimple"); $this-&gt;assertSame(false, DatenCache::load("testCacheSimple", false)); } function testInvalidateWithParams() { $sTestStringEins = "testStringInvalidateWithParams"; $sTestStringZwei = "testStringInvalidateWithParamsZwei"; $aKonfigEins = array(DatenCache::ANLAGEN_ID() =&gt; 1, "Pony" =&gt; false); $aKonfigZwei = array(DatenCache::ANLAGEN_ID() =&gt; 1, "Pony" =&gt; true); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateWithParams", $aKonfigEins, $sTestStringEins)); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateWithParams", $aKonfigZwei, $sTestStringEins)); DatenCache::invalidate("testCacheInvalidateWithParams", $aKonfigEins); $this-&gt;assertSame(false, DatenCache::load("testCacheInvalidateWithParams", $aKonfigEins)); $this-&gt;assertSame($sTestStringEins, DatenCache::load("testCacheInvalidateWithParams", $aKonfigZwei)); $aKonfigDrei = array(DatenCache::ANLAGEN_ID() =&gt; 1, DatenCache::BENUTZER_ID() =&gt; 123, "bob" =&gt; "please"); $aKonfigVier = array(DatenCache::ANLAGEN_ID() =&gt; 2, "Pony" =&gt; true, "bob" =&gt; "please"); $aPartEins = array(DatenCache::ANLAGEN_ID() =&gt; 1); $aPartZwei = array(DatenCache::BENUTZER_ID() =&gt; 123); $aPartDrei = array("bob" =&gt; "please"); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateWithParams", $aKonfigDrei, $sTestStringZwei."1")); DatenCache::invalidate("testCacheInvalidateWithParams", $aPartEins); $this-&gt;assertSame(false, DatenCache::load("testCacheInvalidateWithParams", $aKonfigDrei)); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateWithParams", $aKonfigDrei, $sTestStringZwei."2")); DatenCache::invalidate("testCacheInvalidateWithParams", $aPartZwei); $this-&gt;assertSame(false, DatenCache::load("testCacheInvalidateWithParams", $aKonfigDrei)); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateWithParams", $aKonfigDrei, $sTestStringZwei."3")); DatenCache::invalidate("testCacheInvalidateWithParams", $aPartDrei); $this-&gt;assertSame(false, DatenCache::load("testCacheInvalidateWithParams", $aKonfigDrei)); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateWithParams", $aKonfigEins, $sTestStringEins)); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateWithParams", $aKonfigZwei, $sTestStringEins)); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateWithParams", $aKonfigDrei, $sTestStringEins)); DatenCache::invalidate("testCacheInvalidateWithParams", array(DatenCache::ANLAGEN_ID() =&gt; 1)); $this-&gt;assertSame(false, DatenCache::load("testCacheInvalidateWithParams", $aKonfigEins)); $this-&gt;assertSame(false, DatenCache::load("testCacheInvalidateWithParams", $aKonfigZwei)); $this-&gt;assertSame(false, DatenCache::load("testCacheInvalidateWithParams", $aKonfigDrei)); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateWithParams", $aKonfigEins, $sTestStringEins)); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateWithParams", $aKonfigVier, $sTestStringEins)); DatenCache::invalidate("testCacheInvalidateWithParams", array(DatenCache::ANLAGEN_ID() =&gt; 1)); $this-&gt;assertSame(false, DatenCache::load("testCacheInvalidateWithParams", $aKonfigEins)); $this-&gt;assertSame($sTestStringEins, DatenCache::load("testCacheInvalidateWithParams", $aKonfigVier)); } function testCleanup() { $this-&gt;assertSame(true, DatenCache::save("testCacheSimple", false, "testString", "-5 seconds")); $this-&gt;assertSame(true, DatenCache::save("testCacheSimpleBleibt", false, "testString", "+30 seconds")); DatenCache::cleanup(); $this-&gt;assertSame("testString", DatenCache::load("testCacheSimpleBleibt", false)); $this-&gt;assertSame(false, DatenCache::load("testCacheSimple", false)); // Direkt auf der DB Prüfen ob der Datensatz wiklich gelöscht wurde und nicht nur ausgelaufen ist $this-&gt;assertSame( array(), McDb::getConnection(DB_MC_CACHES)-&gt;getRow( "SELECT * FROM mc_caches.T_DATEN_CACHE WHERE PARAMETER = ? AND VALUE = ?", "NAME", "testCacheSimple" ) ); } function testCleanupWithParam() { $aKonfig = array(DatenCache::ANLAGEN_ID() =&gt; 1); $this-&gt;assertSame(true, DatenCache::save("testCacheSimple", $aKonfig, "testString", "+120 seconds")); DatenCache::cleanup(); $this-&gt;assertSame("testString", DatenCache::load("testCacheSimple", $aKonfig)); } function testInvalidateByParam() { $mValue1 = 1; $mValue2 = 2; $aKonfigEins = array(DatenCache::ANLAGEN_ID() =&gt; $mValue1); $aKonfigZwei = array(DatenCache::ANLAGEN_ID() =&gt; $mValue2); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateByParam", $aKonfigEins, "testString")); $this-&gt;assertSame(true, DatenCache::save("testCacheInvalidateByParam2", $aKonfigZwei, "testString2")); DatenCache::invalidateByParam(DatenCache::ANLAGEN_ID()); $this-&gt;assertSame(false, DatenCache::load("testCacheInvalidateByParam", $aKonfigEins)); $this-&gt;assertSame(false, DatenCache::load("testCacheInvalidateByParam2", $aKonfigZwei)); $this-&gt;assertSame(true, DatenCache::save("testCacheSimple", $aKonfigEins, "testString")); $this-&gt;assertSame(true, DatenCache::save("testCacheSimple2", $aKonfigZwei, "testString2")); DatenCache::invalidateByParam(DatenCache::ANLAGEN_ID(), $mValue1); $this-&gt;assertSame(false, DatenCache::load("testCacheSimple", $aKonfigEins)); $this-&gt;assertSame("testString2", DatenCache::load("testCacheSimple2", $aKonfigZwei)); } function testInvalidateByParamLike() { $mValue1 = "I wan't a Pony"; $mValue2 = "No Pony for you !"; $mValue3 = "xxx"; $this-&gt;assertSame(true, DatenCache::save("PonyCache", array("PonyParam" =&gt; $mValue1), "test1")); $this-&gt;assertSame(true, DatenCache::save("PonyCache", array("PonyParam" =&gt; $mValue2), "test2")); $this-&gt;assertSame(true, DatenCache::save("PonyCache", array("PonyParam" =&gt; $mValue3), "test3")); DatenCache::invalidateByParam("PonyParam", "%Pony%", true); $this-&gt;assertSame(false, DatenCache::load("PonyCache", array("PonyParam" =&gt; $mValue1))); $this-&gt;assertSame(false, DatenCache::load("PonyCache", array("PonyParam" =&gt; $mValue2))); $this-&gt;assertSame("test3", DatenCache::load("PonyCache", array("PonyParam" =&gt; $mValue3))); } /** * @expectedException PHPUnit_Framework_Error */ function testInvalidSaveTime() { $this-&gt;assertSame(false, DatenCache::save("testFail", null, "test1", "invalidStrtotime")); } function testInvalidSaveTimeReturn() { $this-&gt;assertSame(false, @DatenCache::save("testFail", null, "test1", "invalidStrtotime")); } } </code></pre>

47

<p>I am currently developing a custom CMS being built on top of Codeigniter and was wondering if you can spot any flaws in my page fetching model code. The page fetching model is not entirely complete but the main functionality for retrieving a page is done, as well as retrieving modules assigned to a page (a module is really just a widget).</p> <p>Can this model be better in some parts, perhaps in relation to the joins I am doing? although not really joins, but multiple queries to pull out bits of related info the pages like modules and media.</p> <pre><code>&lt;?php class Mpages extends CI_Model { public function __construct() { parent::__construct(); } public function fetch_page($page_slug = 'home') { $db = $this-&gt;db; $query = $db -&gt;where('page_status', 1) -&gt;where('page_slug', strtolower($page_slug)) -&gt;get('pages') -&gt;result_array(); $page_id = $query[0]['id']; $query['modules'] = $db -&gt;select('modules.module_name, modules.module_slug, modules.id moduleid') -&gt;where('page_id', $page_id) -&gt;join('pages_modules lpm', 'moduleid = lpm.module_id') -&gt;order_by('module_order', 'asc') -&gt;get('modules') -&gt;result_array(); /*$query['media'] = $db -&gt;select('lucifer_media.media_file_name, lucifer_media.media_file_extension, lucifer_media.media_directory') -&gt;join('lucifer_pages_media', 'lucifer_pages_media.page_id = '.$page_id.'') -&gt;get('lucifer_media') -&gt;result_array();*/ if ($query) { return $query; } else { return false; } } public function fetch_navigation() { $result = $this-&gt;db-&gt;order_by("nav_order", "asc")-&gt;where('published', 1)-&gt;get('navigation')-&gt;result_array(); return $result; } public function fetch_layout($id) { $result = $this-&gt;db-&gt;where('id', $id)-&gt;get('layouts')-&gt;result_array(); return $result[0]; } } ?&gt; </code></pre>

48

<p>Here's my <code>bootstrap.php</code> for my PHP/MySQL/Doctrine app. It's my first PHP app so I'm interested in learning from the experience of others how this could be improved - security-wise, performance-wise, or otherwise.</p> <pre><code>//------------------------------------------------------------------------- // Define global constants define('ROOT_PATH', dirname(__FILE__) . '/'); define('URL_BASE', 'http://localhost/myapp/public/'); define('LIB_PATH', 'C:\\wamp\\www\\lib\\'); define('OPENID_PATH', 'C:\\wamp\www\\lib\\lightopenid.git\\openid.php'); //------------------------------------------------------------------------- // Bootstrap Doctrine.php, register autoloader, specify // configuration attributes and load models. require_once(LIB_PATH . 'doctrine12/lib/Doctrine.php'); spl_autoload_register(array('Doctrine', 'autoload')); $manager = Doctrine_Manager::getInstance(); //------------------------------------------------------------------------- // Define database connection $dsn = 'mysql:dbname=mydb;host=127.0.0.1'; $user = 'xxx'; $password = 'yyy'; $dbh = new PDO($dsn, $user, $password); $conn = Doctrine_Manager::connection($dbh); //------------------------------------------------------------------------- // Set defaults $manager-&gt;setAttribute(Doctrine::ATTR_DEFAULT_COLUMN_OPTIONS, array('type' =&gt; 'string', 'length' =&gt; 255, 'notnull' =&gt; true)); $conn-&gt;setAttribute(Doctrine_Core::ATTR_QUOTE_IDENTIFIER, true); $manager-&gt;setAttribute(Doctrine_Core::ATTR_AUTO_ACCESSOR_OVERRIDE, true); // Don't load a model until it's needed (causes problems when this is on) //$manager-&gt;setAttribute(Doctrine_Core::ATTR_MODEL_LOADING, Doctrine_Core::MODEL_LOADING_CONSERVATIVE); //------------------------------------------------------------------------- // Import model objects Doctrine_Core::loadModels(ROOT_PATH . 'app/models/generated'); // have to load base classes first Doctrine_Core::loadModels(ROOT_PATH . 'app/models'); </code></pre>

49

<p>I'm making a "guess that tune" game in Visual Basic 6 that is supposed to play each song in a random order:</p> <pre><code>' from frmGuessGame.frm Private Sub Swap(ByRef Value1 As Variant, ByRef Value2 As Variant) Dim Temporary As Variant Temporary = Value1 Value1 = Value2 Value2 = Temporary End Sub Private Sub ShuffleList() Dim LoopCtr As Integer, SwapWith As Integer For LoopCtr = LBound(InnerPlaylist) To UBound(InnerPlaylist) SwapWith = (Rnd * (UBound(InnerPlaylist) - LBound(InnerPlaylist))) + LBound(InnerPlaylist) Swap InnerPlaylist(LoopCtr), InnerPlaylist(SwapWith) Next End Sub </code></pre> <p>My initialization function does include the <code>Randomize</code> statement, so it should be a good, even shuffle.</p> <pre><code>' from mdiMain.frm Private Sub MDIForm_Load() 'initialize pseudo-random number generator Randomize frmMusiguess.Show frmSplash.Show End Sub </code></pre> <p>I'm not sure, however, that this is the best way to do it. Am I on the right track?</p>

50

<p>I implemented the Shamos-Hoey algorithm to check if a closed shape is self-intersected. Is this algorithm ok in terms of performance?</p> <pre><code>public boolean isSelfIntersected() { Set&lt;Line2D&gt; plines = new HashSet&lt;Line2D&gt;(); for (Path2D ps : this.getPath()) { PathIterator p_it = ps.getPathIterator(null, /*flatness*/ 1); List&lt;Line2D&gt; estPath = new ArrayList&lt;Line2D&gt;(); while (!p_it.isDone()) { p_it.next(); double[] coords = new double[6]; int s = p_it.currentSegment(coords); if (s == PathIterator.SEG_LINETO) { if (estPath.size() != 0) { Point2D pp = estPath.get(estPath.size() - 1).getP2(); estPath.add(new Line2D.Double(pp, new Point2D.Double(coords[0],coords[1]))); } else { estPath.add(new Line2D.Double(new Point2D.Double(), new Point2D.Double(coords[0],coords[1]))); } } } for (Line2D lq : estPath) { plines.add(tweakLine(lq)); } } return ShamosHoeyAlgorithm(plines); } /** * Moves first point of the line by 0.0000001 of it's length. * @return */ static Line2D tweakLine(Line2D l) { Line2D ql = new Line2D.Double( l.getX1() + 0.0000001*(l.getX2() - l.getX1()), l.getY1() + 0.0000001*(l.getY2() - l.getY1()), l.getX2() - 0.0000001*(l.getX2() - l.getX1()), l.getY2() - 0.0000001*(l.getY2() - l.getY1())); return ql; } public class ShamosHoeyAlgorithm { public static boolean ShamosHoeyAlgorithm(Collection&lt;Line2D&gt; lines) { List&lt;AlgEvent&gt; events = new ArrayList&lt;AlgEvent&gt;(lines.size() * 2); for (Line2D li : lines) { if (li.getX1() &lt; li.getX2()) { Line2D l = new Line2D.Double(li.getP1(), li.getP2()); events.add(new AlgEvent(l, true)); events.add(new AlgEvent(l, false)); } else if (li.getX1() &gt; li.getX2()) { Line2D l = new Line2D.Double(li.getP2(), li.getP1()); events.add(new AlgEvent(l, true)); events.add(new AlgEvent(l, false)); } else { if (li.getY1() &lt; li.getY2()) { Line2D l = new Line2D.Double(li.getP1(), li.getP2()); events.add(new AlgEvent(l, true)); events.add(new AlgEvent(l, false)); } else if (li.getY1() &gt; li.getY2()) { Line2D l = new Line2D.Double(li.getP2(), li.getP1()); events.add(new AlgEvent(l, true)); events.add(new AlgEvent(l, false)); } else { return true; } } } Collections.sort(events, new AlgEvtComparator()); TreeSet&lt;Line2D&gt; sl = new TreeSet&lt;Line2D&gt;(new LineComparator()); for (AlgEvent e : events) { if (e.isStart) { Line2D nl = e.line; Line2D above = sl.higher(nl); if (above != null) { if (above.intersectsLine(nl)) { return true; } } Line2D below = sl.lower(nl); if (below != null) { if (below.intersectsLine(nl)) { return true; } } sl.add(nl); } else { Line2D nl = e.line; Line2D above = sl.higher(nl); Line2D below = sl.lower(nl); sl.remove(nl); if (above != null &amp;&amp; below != null) { if (above.intersectsLine(below)) { return true; } } } } return false; } static class AlgEvent { public Line2D line; public boolean isStart; AlgEvent(Line2D l, boolean isStart) { line = l; this.isStart = isStart; } Point2D getPoint() { return (isStart) ? line.getP1() : line.getP2(); } double getX() { return (isStart) ? line.getX1() : line.getX2(); } double getY() { return (isStart) ? line.getY1() : line.getY2(); } @Override public String toString() { return "start = " + isStart + ", point = " + this.getPoint() + ", line = " + line.getP1() + " : " + line.getP2(); } } static class AlgEvtComparator implements Comparator&lt;AlgEvent&gt; { public int compare(AlgEvent o1, AlgEvent o2) { if (o1.getX() &lt; o2.getX()) { return -1; } else if (o1.getX() &gt; o2.getX()) { return 1; } else { if (o1.getY() &lt; o2.getY()) { return -1; } else { return 1; } } } } /** * Class to compare lines, to ensure above-below order. */ static class LineComparator implements Comparator&lt;Line2D&gt; { public int compare(Line2D o1, Line2D o2) { if (o1.getY1() &lt; o2.getY1()) { return -1; } else if (o1.getY1() &gt; o2.getY2()) { return 1; } else { if (o1.getY2() &lt; o2.getY2()) { return -1; } else if (o1.getY2() &gt; o2.getY2()) { return 1; } else { return 0; } } } } } </code></pre>

69

<p>I've implemented a PID controller, but seeing as I'm not an expert in control theory, have I missed any edge cases?</p> <pre><code>public class PIDController { public enum PIDMode { Manual, Auto, } public enum PIDAction { Indirect, Direct, } public PIDMode Mode { get; set; } public PIDAction Action { get; set; } public double Proportional { get; set; } public double Integral { get; set; } public double Derivative { get; set; } public double Minimum { get; set; } public double Maximum { get; set; } public double DeltaMinimum { get; set; } public double DeltaMaximum { get; set; } private double _ProportionalTerm; private double _Integrator; private double _Derivator; public double Setpoint { get; set; } private double _Feedback; public double Feedback { get { return _Feedback; } } public void Calculate(double Input, long Time) { double output; // Compute the error value double Error = Setpoint - Input; if (Mode == PIDMode.Auto) { if (Action == PIDAction.Direct) Error = 0 - Error; // Compute the proportional component _ProportionalTerm = 1000.0f * (Error - _Derivator) / (double)Time; // Compute the integrator component, clamped to min/max delta movement _Integrator += (float)Error * (float)Time / 1000.0f; if (_Integrator &lt; DeltaMinimum) _Integrator = DeltaMinimum; if (_Integrator &gt; DeltaMaximum) _Integrator = DeltaMaximum; // Add the proportional component output = (Proportional * Error); // Add the integral component output += Integral * _Integrator; // Add the derivative component output += Derivative * _ProportionalTerm; // Clamp output to min/max if (output &lt; Minimum) output = Minimum; if (output &gt; Maximum) output = Maximum; } else { output = Input; } // Store values _Derivator = Error; // Returns the result _Feedback = output; } } </code></pre>

72

<p>This plugin is written in jQuery and is made to support <a href="http://codeigniter.com" rel="nofollow">the codeigniter framework</a>. It is an ajax powered table pagination plugin designed to provide only that. You should be able to use almost any other table scripts with this plugin.</p> <pre><code>(function($){ $.fn.extend({ tpaginate: function(options) { //Settings list and the default values var defaults = { page: 0, url : null, rows: 20, nodata: 'The table is empty!', actions: true }; var table; var foot; var body; var curpagespan; var totpagespan; var oldbody; var replaced = false; var options = $.extend(defaults, options); return this.each(function() { table = this; foot = $(table).find(' &gt; tfoot &gt; tr &gt; td'); body = $(table).find(' &gt; tbody'); create_footer(foot); curpagespan = foot.find(' &gt; #table_pagecount &gt; span#page'); totpagespan = foot.find(' &gt; #table_pagecount &gt; span#page_total'); curpagespan.html(0); totpagespan.html(0); $('#searchButton').click(function(){ var term = $('#search').val(); if(term.length &gt;= 3){ if(replaced) load_data(1, term, true, false); else load_data(1, term, true, true); } }); $('#search').keyup(function(){ if($(this).val() == ''){ create_tbody(false, false, true); } }); }); function create_footer() { var pagecount = $('&lt;div id="table_pagecount"&gt;Page &lt;span id="page"&gt;&lt;/span&gt; of &lt;span id="page_total"&gt;&lt;/span&gt;&lt;/div&gt;'); var pager = $('&lt;div id="table_pageination"&gt;&lt;a class="link" id="first" style="display:none;"&gt;First&lt;/a&gt;&lt;a class="link" id="prev" style="display:none;"&gt;Prev&lt;/a&gt;&lt;span id="pages"&gt;&lt;/span&gt;&lt;a class="link" id="next" style="display:none;"&gt;Next&lt;/a&gt;&lt;a class="link" id="last" style="display:none;"&gt;Last&lt;/a&gt;&lt;/div&gt;'); foot.append(pagecount); foot.append(pager); load_data(1, '', true); } function current_page(page){ curpagespan.html(page); } function total_page(page){ totpagespan.html(Math.ceil(page/options.rows)); } function load_data(page, search, action, save){ if(save == null) save = false; else save = true; $('#table_pageination a.link').unbind('click'); search = (search == null ? '' : search); var start = (page-1)*options.rows; if(page == 1) start = 0; var url = options.url+'/'+start+'/'+action+'/'+search; $.ajax({ url: url, success: function(data) { if(data.total != 0){ current_page(page); total_page(data.total); create_tbody(data.members, save); update_pages(page, Math.ceil(data.total/options.rows)); } else{ current_page(0); total_page(0); foot.find(' &gt; #table_pageination &gt; #pages').html('&lt;a class="link"&gt;0&lt;/a&gt;'); var newtr = $('&lt;tr&gt;&lt;/tr&gt;'); var newtd = $('&lt;td style="font-weight:bold;text-align: center;"&gt;&lt;/td&gt;').attr('colspan', foot.attr('colspan')).text(options.nodata); body.html(newtr.append(newtd)); } } }); } function create_tbody(rows, save, revert){ if(save == true){ oldbody = body.html(); replaced = true; } var newbody = $('&lt;tbody /&gt;'); if(revert == null){ for(var i in rows){ var row = $('&lt;tr /&gt;'); for(var j in rows[i]){ if(j != 'id' &amp;&amp; j != 'actions') row.append('&lt;td class="'+j+'td"&gt;'+(rows[i][j] == null ? '' : rows[i][j])+'&lt;/td&gt;'); if(j == 'actions' &amp;&amp; rows[i][j] != null &amp;&amp; options.actions) row.append(rows[i][j]); } newbody.append(row); } } else{ newbody.html(oldbody); replaced = false; } body.html(newbody.html()); $(table).trigger("update"); } function update_pages(page, total){ foot.find(' &gt; #table_pageination &gt; #pages').html(ranger(page, 5, total)); if(page == 1){ foot.find(' &gt; #table_pageination &gt; a#first').fadeOut('slow'); foot.find(' &gt; #table_pageination &gt; a#prev').fadeOut('slow'); } else{ foot.find(' &gt; #table_pageination &gt; a#first').attr('rel', 1).fadeIn('slow'); if(page != 2) foot.find(' &gt; #table_pageination &gt; a#prev').attr('rel', page-1).fadeIn('slow'); } if(total != page){ foot.find(' &gt; #table_pageination &gt; a#last').attr('rel', total).fadeIn('slow'); if(total != page+1) foot.find(' &gt; #table_pageination &gt; a#next').attr('rel', ++page).fadeIn('slow'); } else{ foot.find(' &gt; #table_pageination &gt; a#last').attr('rel', total).fadeOut('slow'); foot.find(' &gt; #table_pageination &gt; a#next').attr('rel', total).fadeOut('slow'); } $('#table_pageination a.link').click(function(){ replaced = false; load_data($(this).attr('rel'), '', true); }); } function ranger(num, range, max) { var left = num*1; var right = num*1; while (right - left &lt; range * 2) { if (right + 1 &lt;= max) right++; if (left - 1 &gt; 0) left--; if (right == max &amp;&amp; left == 1) break; } var str = ''; for (var i = left; i &lt;= right; i++) { if(i != num) str += '&lt;a class="link" rel="'+i+'"&gt;'+i+'&lt;/a&gt;'; if(i == num) str += '&lt;a rel="nolink"&gt;'+i+'&lt;/a&gt;'; } return str; } } }); })(jQuery); </code></pre>

77

<p>Is this the best way to implement this pattern in C#?</p> <pre><code>public sealed class Singleton { private static readonly Singleton instance = new Singleton(); public static Singleton Instance { get { return instance; } } static Singleton() {} private Singleton() {} } </code></pre>

79

<p>I'm listing elements with a <code>foreach</code>, and I would like to enclose items in something tag <code>n</code> by <code>n</code>:</p> <pre><code>$i = 0; $open = $done = TRUE; $n = 3; $opening = "&lt;div&gt;"; $closing = "&lt;/div&gt;"; $names = array("Doc", "Marty", "George", "Lorraine", "Einstein", "Biff"); foreach($names as $name) { /** $condition was not a bool. My fault. */ if($open &amp;&amp; !($i % n)) { print $opening; $open = FALSE; $done = !$open; } elseif(!($i % n)) $done = FALSE; /** print element. */ print $name; if(!$open &amp;&amp; !($i % n) &amp;&amp; !$done) { print $closing; $open = TRUE; $done = !$open; } $i++; } </code></pre> <p>Do you think this snippet can be improved? It would be better to have fewer check variables such as <code>$open</code> or <code>$done</code>.</p>

82

<p>I was wondering for quite some time how to clean up the below code without blowing it up any further. The extension of the classes is the main concern here, it looks a bit too much like magic. That's mainly because it has to handle all the different cases, and I haven't figured out a way to reduce the code in a meaningful fashion here.</p> <p>Maybe I'm paranoid and the code is just fine, but I'd still love to get some feedback on it.</p> <p>The original code and test cases are <a href="https://github.com/BonsaiDen/neko.js" rel="nofollow">here</a>.</p> <pre><code>function is(type, obj) { return Object.prototype.toString.call(obj).slice(8, -1) === type; } function copy(val) { /* ...make shallow copy */ } function wrap(caller, obj) { obj = obj || Function.call; return function() { return obj.apply(caller, arguments); }; } function Class(ctor) { // ...default ctor stuff here.... function clas(args) { /* ...actual instance ctor stuff... */} var proto = {}; clas.init = wrap(ctor); // extend needs to be reduced in width, it easily goes over 80 columns // without some ugly if statements clas.extend = function(ext) { if (is('Function', ext)) { return ext.extend(proto); // holy closure! } for (var e in ext) { if (!ext.hasOwnProperty(e)) { continue; // a bit ugly imo, but it helps to prevent the indentation // from blowing up } // this needs some refactoring, it creates bound and unbound var val = ext[e], func = is('Function', val); if (/^\$/.test(e)) { // statics proto[e] = copy(val); clas[e] = clas.prototype[e] = func ? wrap(clas, val) : val; } else if (func) { clas[e] = wrap(proto[e] = clas.prototype[e] = val); } } return clas; }; // this could also need some clean up I suppose for (var i = ctor.hasOwnProperty('init') ? 0 : 1, l = arguments.length; i &lt; l; i++) { var arg = arguments[i]; is('Object', arg) ? clas.extend(arg) : arg.extend(clas); } return clas; } </code></pre>

85

<p>I'm new to Postgres and PostGIS, but not to geospatial applications.</p> <p>I have a table loaded up with graph data in the form of links (edges). The link database has about <strong>60,000,000</strong> rows. I am trying to extract the nodes to allow for quicker searching. For some of my proof-of-concept work I was able to use the link table for the searches, but there will be lots of duplicates, and there's no guarantee that either the source column or the target column contains all nodes.</p> <p>This is Postgres &amp; PostGIS, so I am also using the table to cache a geometry->geography conversion. Yes I do need to use geography fields. I'm also copying the geometry information "just in case".</p> <p>Table creation SQL:</p> <pre><code>-- Recreate table and index DROP TABLE IF EXISTS nodes; CREATE TABLE nodes (node integer PRIMARY KEY, geog geography(POINT,4326) ); CREATE INDEX geogIndex ON nodes USING GIST(geog); SELECT AddGeometryColumn('nodes', 'geom', 4326, 'POINT', 2); -- Insert all unique nodes from the source column INSERT INTO nodes (node,geog,geom) SELECT DISTINCT ON (source) source,geography( ST_Transform(geom_source,4326)),geom_source FROM view_topo; -- Insert any nodes in the target column that we don't have already INSERT INTO nodes (node,geog,geom) SELECT DISTINCT ON (target) target,geography( ST_Transform(geom_target,4326)),geom_target FROM view_topo WHERE NOT EXISTS( SELECT 1 FROM nodes WHERE nodes.node = view_topo.target); VACUUM ANALYZE; </code></pre> <p>I left the first <code>INSERT</code> running overnight and it took about 2-3hrs to run. This resulted in about <strong>40,000,000</strong> unique nodes being added.</p> <p>I have just enabled the second <code>INSERT</code> and the <code>VACUUM ANALYZE</code>. I am expecting it to take until at least lunchtime.</p> <p>Luckily this is only a batch job that has to be executed once after I've loaded a new link table, but is there a better way? Is there a faster way?</p>

92

<p>I have written a method to tokenize HTTP request paths such as <code>/employee/23/edit</code>:</p> <pre><code>protected void compile(String path){ int mark=0; for(int i=0; i&lt;path.length(); ++i){ if(path.charAt(i)==DELIM){ if(mark!=i) tokens.add(path.substring(mark,i)); mark=i+1; } else if(path.length()==i+1){ tokens.add(path.substring(mark,i+1)); } } } </code></pre> <p>And a method to tokenize the consumer of these paths such as <code>/employee/[id]/edit</code>:</p> <pre><code>protected void compile(String path){ int mark=0; boolean wild=false; for(int i=0; i&lt;path.length(); ++i){ if(!wild){ if(path.charAt(i)==DELIM){ if(mark!=i) tokens.add(path.substring(mark,i)); mark=i+1; } else if(path.length()==i+1){ tokens.add(path.substring(mark,i+1)); } else if(path.charAt(i)=='['){ wild=true; } } else if(path.charAt(i)==']'){ tokens.add("?"); wild=false; mark=i+1; } } } </code></pre> <p>The idea here is that there will be an implicit variable called <code>id</code> with the value <code>23</code>. However, that isn't here nor there. How does my approach look? Can it be improved? Also: <code>DELIM = '/'</code>.</p> <p>This is more-or-less an exercise in writing a parser, which is why I didn't use <code>String#split()</code>.</p>

109

<p>I have written this (truncated) code to fetch some tweets:</p> <pre><code> dispatch_async(dispatch_get_global_queue(0, 0), ^{ [[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:YES]; NSString *JSONStr = [NSString stringWithContentsOfURL:[NSURL URLWithString:@"http://search.twitter.com/search.json?q=haak&amp;lang=nl&amp;rpp=100"] encoding:NSUTF8StringEncoding error:nil]; if (!JSONStr) { [[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:NO]; return; } /*... PARSING ETC ...*/ dispatch_sync(dispatch_get_main_queue(), ^{ [delegate didReceiveTweets:foundTweets]; }); [[UIApplication sharedApplication] setNetworkActivityIndicatorVisible:NO]; }); </code></pre> <p>Note the lines from <code>dispatch_sync(dispatch_get_main_queue(), ^{</code> to <code>});</code>. This will update the UI.</p> <p>Is this the good way to do it, or are there better ways than using <code>dispatch_sync</code> within a <code>dispatch_async</code>? Or should I not do this at all? Should I also send <code>setNetworkActivityIndicatorVisible:</code> from within the main thread?</p> <p>The reason I'm not using <code>NSURLConnection</code> is because this code comes from a class method, so I need to create an object containing the delegate for the <code>NSURLConnection</code>, which seems overkill to me.</p>

112

<p>I have a Perl application that allows the user to choose between two different formats for data output (and there will likely be more in the near future). In the heart of the algorithm, the code makes a call to a print subroutine.</p> <pre><code>my $stats = analyze_model_vectors( $reference_vector, $prediction_vector ); print_result( $stats, $tolerance ); </code></pre> <p>The <code>print_result</code> subroutine simply calls more specific methods.</p> <pre><code>sub print_result { if($outformat eq "text") { print_result_text(@_); } elsif($outformat eq "xml") { print_result_xml(@_); } else { # Should not reach this far if input checking is done correctly printf(STDERR "Error: unsupported output format '%s'\n", $outformat); } } </code></pre> <p>Is this good practice? What other alternatives are there and what are their pros/cons? I could think of the following alternatives.</p> <ul> <li>Test for output format in the heart of the algorithm, and call the appropriate printing subroutine there.</li> <li>I've never used subroutine references before, but perhaps when I could store a reference to the correct subroutine in a scalar variable and call the print method with that scalar in the heart of the algorithm.</li> <li>Place code for all output formats in a single subroutine, separated by <code>if/elsif/else</code> statements.</li> </ul> <p>Keep in mind there may be more output formats required in the near future.</p>

115

<p>So I have a series of objects, which I will call Impl1, Impl2, and Impl3. They each implement an interface, called IImpl. I have a Factory class who's task is to retrieve the ImplX which is appropriate for a given circumstance, and pass it on to its callers. So the code in the factory looks like:</p> <pre><code>public IImpl GetInstance(params object[] args) { if (args[0]=="Some Value") return new IImpl1(); else if (args[0]=="Other Value") return new IImpl2(args[1]); else return new IImpl3(args[1]); } </code></pre> <p>So depending on the arguments passed in, different instances are selected. All well and good and works ok. The problem now is, that I have a class which needs to call this factory method. It has no references to IImplX, which is good, but it winds up having to know exactly how to construct the input array to GetInstance, in order to ensure it receives the correct kind of instance. Code winds up looking like:</p> <pre><code>switch (_selectedInputEnum) { case InputType.A: myIImplInst = Factory.GetInstance("Some Value"); case InputType.B: myIImplInst = Factory.GetInstance("Other Value",this.CollectionB); case InputType.C: myIImplInst = Factory.GetInstance("Third Value",this.CollectionC); } </code></pre> <p>This feels very redundant, and off somehow. What would be the best way to abstract the actual parameters of the factory? I feel like with the above switch statement, I am strongly coupled to the implemenations of IImplx, even if I don't have a direct reference.</p>

128

<p><em>Inspired by <a href="https://codereview.stackexchange.com/q/97">this question</a>, but hopefully not a duplicate.</em></p> <p>I understand that the Law of Demeter is very useful in case of services interacting with other services, for example it's much easier to mock the other services in unit tests. What about services interacting with data models, though?</p> <p>Let's say I have a hierarchy of immutable classes:</p> <pre><code>public final class Document { private final List&lt;Page&gt; pages; // Constructor, getter, ... } public final class Page { private final List&lt;Paragraph&gt; paragraphs; // Constructor, getter, ... } public final class Paragraph { private final List&lt;Line&gt; lines; // Constructor, getter, ... } </code></pre> <p>Let's say I want to do something with certain lines in a document <code>doc</code>:</p> <pre><code>public void doSomething(Document doc) { for (Page page : doc.getPages()) { for (Paragraph para : page.getParagraphs()) { for (Line line : para.getLines()) { if (someCondition(line)) { someAction(line); } } } } </code></pre> <p>Now, as far as I understand, the above code doesn't obey the Law of Demeter. However, I don't want to force the law at all cost and clutter the model (here, the <code>Document</code> class) with tens of methods like:</p> <pre><code>public List&lt;Line&gt; filterWrtSomeCondition(); public List&lt;Line&gt; filterWrtSomeOtherCondition(); </code></pre> <p>Or maybe there's a third way? I suspect that the Law of Demeter applies primarily to services interacting with other services. Is it a valid interpretation?</p>

131

<p>Code Review - Stack Exchange is for <strong>sharing code from projects you are working on</strong> for peer review. If you are looking for feedback on a specific working piece of code from your project in the following areas&hellip;</p> <ul> <li>Best practices and design pattern usage</li> <li>Security issues</li> <li>Performance</li> <li>Correctness in unanticipated cases</li> </ul> <p>then you are in the right place!</p> <p>However, if your question is not about a particular piece of code and instead is a generally applicable question about &hellip;</p> <ul> <li>Tools, best practices, improving, or conducting code reviews</li> <li>Trouble-shooting, debugging, or understanding code snippets</li> <li>Higher-level architecture and design of software systems</li> </ul> <p>then your question is off-topic for this site.</p> <h3>I'm confused! What questions are on-topic for this site?</h3> <p>Simply ask yourself the following questions. To be on-topic the answer must be yes to all questions:</p> <ol> <li>Does my question contain code? (Please include the code in the question, not a link to it)</li> <li>Did I write that code?</li> <li>Is it actual code from a project rather than pseudo-code or example code?</li> <li>Do I want the code to be good code, (i.e. not code-golfing, obfuscation, or similar)</li> <li>To the best of my knowledge, does the code work?</li> <li>Do I want feedback about any or all facets of the code?</li> </ol> <p>If you answered yes to all the above questions, your question is on-topic for Code Review.</p> <h3>Make sure you include your code in your question</h3> <p>This site is for code reviews, which are hard to do when the code is behind a link somewhere out there on the internet. If you want a code review, you <em>must</em> post the relevant snippets of code <em>in your question</em>. It is fine to post a "see more" link (though, do be careful &mdash; very few reviewers will be willing to click through and read thousands of lines of your code), but the most important parts of the code <em>must</em> be placed directly in the question.</p> <h3>Reviewers may comment on any part of the code.</h3> <p>Feel free to call attention to specific areas you are concerned about (performance, formatting, etc). However, <em>any</em> aspect of the code posted is fair game for feedback and criticism.</p> <h3>What? Questions <em>about</em> code reviews are off topic?</h3> <p>Conducting code reviews is an important skill, much like any other programming discipline. These "whiteboard"-style questions are best asked on <a href="http://programmers.stackexchange.com">Programmers Stack Exchange</a>.</p>

135

<p>Would this function be sufficient enough to remove all malicious code and foreign characters from a string?</p> <pre><code>//Clean the string $out = ltrim($do); $out = rtrim($out); $out = preg_replace('/[^(\x20-\x7F)]*/','', strip_tags($out)); </code></pre> <p>This data is not going into a SQL database, so I dont have to worry about sql injection attempts. Is there any way to improve my code and make it more efficient?</p> <p>This function would clean any user inputted data (forms, and ?), and then save it do a database. This would be used in a global sanitizing function.</p>

136

<p>I don't like the fact that I am selecting all the points, even though I only care about the count of them.</p> <p>Which of the <code>from</code> parts should appear first, if it even matters?</p> <pre><code>var count = (from type in ValidTypes() from point in GetData(type) where point.Radius &gt; referencePoint.Radius &amp;&amp; point.Theta &gt; referencePoint.Theta select point).Count() </code></pre> <p><code>ValidTypes()</code> returns a few types, about 5.</p> <p><code>GetData(type)</code> may return many points, possibly 100,000.</p> <p>This query is counting the number of points that have both a larger theta and a larger radius than a given point.</p> <p>Is there a way to write this faster or more readable?</p>

138

<p>This is a function I wrote yesterday and have tested with lots of input. It's been committed and is in use, but no review was done, so it seems like a good candidate for Code Review: it could be more readable and maybe refactored into simpler functions.</p> <p>Its purpose is to give the longest common path and a string listing filenames for lists of dictionaries with full file paths. It's used to process <a href="https://api.bitbucket.org/1.0/repositories/jespern/django-piston/changesets/c9fe89f3ec79/">Bitbucket API results</a>.</p> <pre><code>import os.path import py # Used for other functions, listed for possible use in refactoring def getpaths(files, listfiles=False): """For a list of files, a common path prefix and optionally list filenames Returns a tuple (common_prefix, filenames): common_prefix: Longest common path to all files in the input. If input is a single file, contains full file path. Slash-terminated if present and directory, empty string otherwise. filenames: String containing the names of modified files, in the format " M(file1, file2)" if listfiles=True, empty string if either listfiles=False or no file was modified. """ # Handle empty input if not files: return '', '' files = [f['file'] for f in files] if not any(files): return '', '' dirname = os.path.dirname basename = os.path.basename common_prefix = [dirname(f) for f in files] # Single file, show its full path if len(files) == 1: common_prefix = files[0] listfiles = False else: common_prefix = [path.split(os.sep) for path in common_prefix] common_prefix = os.sep.join(os.path.commonprefix(common_prefix)) if common_prefix and not common_prefix.endswith('/'): common_prefix += '/' if listfiles: filenames = [basename(f) for f in files if f and basename(f)] filenames = ' M(%s)' % ', '.join(filenames) else: filenames = '' return common_prefix, filenames # Test suite # Don't worry too much about test style, this is informative enough with py.test. # Adequate coverage and readibility are the main concern. # However, if you think a doctest or classic unittest is better, I'm open to change. def test_getpaths(): d = dict barefile = [d(file='file')] distinct = [d(file='path1/file1'), d(file='path2/file2'), d(file='path3/file')] shared = [d(file='path/file1'), d(file='path/file2'), d(file='path/file')] deepfile = [d(file='a/long/path/to/deepfile.py')] slashesfile = [d(file='/slashesfile/')] slashleft = [d(file='/slashleft')] slashright = [d(file='slashright/')] nocommon = distinct + [d(file='path4/file')] nocommonplusroot = distinct + barefile common = [d(file='some/path/to/file'), d(file='some/path/to/deeper/file'), d(file='some/path/to/anotherfile'), d(file='some/path/to/afile')] commonplusroot = shared + barefile empty = d(file='') nocommonplusempty = distinct + [empty] commonplusempty = shared + [empty] nocommonplusslash = distinct + [d(file='path4/dir/')] commonplusslash = shared + [d(file='path/dir/')] pypydoubleslash = [d(file='pypy/jit/metainterp/opt/u.py'), d(file='pypy/jit/metainterp/test/test_c.py'), d(file='pypy/jit/metainterp/test/test_o.py')] nothing = ('', '') # (input, expected output) for listfiles=False files_expected = [([], nothing), ([empty], nothing), ([empty, empty], nothing), (barefile, ('file', '')), (deepfile, ('a/long/path/to/deepfile.py', '')), (slashesfile, ('/slashesfile/', '')), (slashleft, ('/slashleft', '')), (slashright, ('slashright/', '')), (nocommon, nothing), (nocommonplusroot, nothing), (nocommonplusempty, nothing), (common, ('some/path/to/', '')), (commonplusroot, nothing), (commonplusempty, nothing), (nocommonplusslash, nothing), (commonplusslash, ('path/', '')), (pypydoubleslash, ('pypy/jit/metainterp/', '')), ] for f, wanted in files_expected: assert getpaths(f) == wanted # (input, expected output) for listfiles=True files_expected = [([], nothing), ([empty], nothing), ([empty, empty], nothing), (barefile, ('file', '')), (deepfile, ('a/long/path/to/deepfile.py', '')), (slashesfile, ('/slashesfile/', '')), (slashleft, ('/slashleft', '')), (slashright, ('slashright/', '')), (nocommon, ('', ' M(file1, file2, file, file)')), (nocommonplusroot, ('', ' M(file1, file2, file, file)')), (nocommonplusempty, ('',' M(file1, file2, file)')), (common, ('some/path/to/', ' M(file, file, anotherfile, afile)')), (commonplusroot, ('', ' M(file1, file2, file, file)')), (commonplusempty, ('',' M(file1, file2, file)')), (nocommonplusslash, ('',' M(file1, file2, file)')), (commonplusslash, ('path/',' M(file1, file2, file)')), (pypydoubleslash, ('pypy/jit/metainterp/', ' M(u.py, test_c.py, test_o.py)')), ] for f, wanted in files_expected: assert getpaths(f, listfiles=True) == wanted </code></pre> <p>Improvements for both the function and its tests are welcome. For some context, this is how it's used:</p> <pre><code># Here's the kind of data we want to process. The return for listfiles=False # should be ('bit/', ''). For True, # ('bit/', ' M(hook.py, __init__.py, __init__.py, test_hook.py)') commit = { u'files': [{u'file': u'bit/hook.py', u'type': u'modified'}, {u'file': u'bit/__init__.py', u'type': u'added'}, {u'file': u'bit/test/__init__.py', u'type': u'added'}, {u'file': u'bit/test/test_hook.py', u'type': u'added'}] } files = commit.get('files', []) common_prefix, filenames = getpaths(files, True) common_prefix = '/' + common_prefix print '%s%s: ' % (common_prefix, filenames) </code></pre>

142

<p>I do most of my programming in C/C++ and Perl, but I currently learning Fortran. I began by coding up a simple program, something that took me &lt; 5 minutes in Perl (see <a href="http://biostar.stackexchange.com/questions/4993/extracting-set-of-numbers-from-a-file" rel="noreferrer">this thread</a> from BioStar). After working for several hours on a solution in Fortran 95 (teaching myself as I go), I came to this solution.</p> <p>implicit none</p> <pre><code>! Variable definitions integer :: argc integer :: num_digits integer :: i, j integer :: iocode integer :: line_length integer :: value character ( len=256 ) :: infile character ( len=16 ) :: int_format character ( len=16 ) :: int_string character ( len=2048 ) :: line ! Verify and parse command line arguments argc = iargc() if( argc &lt; 1 ) then write(*, '(A, I0, A)') "Error: please provide file name (argc=", argc, ")" stop endif call getarg(1, infile) ! Open input file, croak if there is an issue open( unit=1, file=infile, action='read', iostat=iocode ) if( iocode &gt; 0 ) then write(*, '(A, A, A)') "Error: unable to open input file '", trim(infile), "'" stop endif ! Process the file, print in CSV format do while(1 == 1) ! Read the line, skip if it is empty 100 read( unit=1, fmt='(A)', end=200 ) line line_length = len_trim(line) if( line_length == 0 ) then goto 100 endif ! The first value in the line is a string ! Find string boundaries and print it out i = 0 do while( line(i:i) == ' ' ) i = i+1 end do j = i do while( line(j:j) /= ' ' ) j = j+1 end do write(*, '(A)', advance="no") line(i:j-1) ! Now grab the rest of the integer values ! on the line, multiply them by 3, and print i = j j = 0 do while( i &lt; line_length) do while( line(i:i) == ' ' ) i = i+1 end do j = i do while( j &lt; line_length .and. line(j:j) /= ' ' ) j = j+1 end do int_string = line(i:j-1) read(int_string, '(I)') value value = value*3 write(*, '(A, I0)', advance="no") ",", value i = j j = 0 end do print * end do 200 close( 1 ) end program </code></pre> <p>There is a lot that I don't like about how I've written this program, but it's hard to separate my inexperience with the new syntax from bad practice. One thing in particular that I don't like is my use of labels and the infamous <code>goto</code> statement. I'm interested in any feedback whatsoever, but I'm particularly interested in better ways to handle the control structure of the program (without using the <code>goto</code> statement and <code>end</code> parameter in the <code>read</code> function if possible).</p> <p>The compilers I have access to only support features through f95.</p>

145

<p>It's a little bit more code but I wanted to show the full class. I highlight the points I'd like input after the source.</p> <p>I've cut comments since they where not in English and translated the important ones.</p> <p>The class is inspired by PearDb (too old) and Zend_DB (to cluttered / unfinished at the time) and is used in a inhouse application. I know it's not ideal to write your own database handler (I'd go so far to say it's pretty pointless).</p> <pre><code>&lt;?php class DbStatement { private $oStatement; private $aFieldnames = array(); private $aResultRow = array(); private $aResultSet = array(); private $bMetadata = true; private $bPreparedFetch = false; private $iNumRows = false; private $sQuery; private $aArgs; private $fQuerytime; /** * @throws DbException * @param mysqli $oDb Datenbankverbindung * @param string $sQuery */ public function __construct(mysqli $oDb, $sQuery) { $this-&gt;oStatement = $oDb-&gt;prepare($sQuery); $this-&gt;sQuery = $sQuery; if($this-&gt;oStatement === false) { switch($oDb-&gt;errno) { case 1054: throw new DbNoSuchFieldException($oDb-&gt;error, $oDb-&gt;errno); case 1146: throw new DbNoSuchTableException($oDb-&gt;error, $oDb-&gt;errno); default: throw new DbException( "Prepared Statement could not be created: ". $oDb-&gt;error." (".$oDb-&gt;errno."). Query was: '$sQuery'", $oDb-&gt;errno ); } } } /**#@+ * * @param mixed $mParams,... */ public function execute() { $this-&gt;_execute(func_get_args()); $this-&gt;_done(); } /** * @return null|bool|int|string|float */ public function getOne() { $this-&gt;_execute(func_get_args()); $this-&gt;_fetchRow(); if(isset($this-&gt;aResultSet[0][$this-&gt;aFieldnames[0]])) { return $this-&gt;aResultSet[0][$this-&gt;aFieldnames[0]]; } return null; } /** * @return array */ public function getCol() { $this-&gt;_execute(func_get_args()); $this-&gt;_fetchAll(); $sIndex = $this-&gt;aFieldnames[0]; $aReturn = array(); foreach($this-&gt;aResultSet as $aResultRow) { $aReturn[] = $aResultRow[$sIndex]; } return $aReturn; } /** * @return array */ public function getRow() { $this-&gt;_execute(func_get_args()); $this-&gt;_fetchRow(); if(isset($this-&gt;aResultSet[0])) { return $this-&gt;aResultSet[0]; } return array(); } /** * @return array */ public function getAssoc() { $this-&gt;_execute(func_get_args()); $this-&gt;_fetchAll(); if(isset($this-&gt;aFieldnames[0]) &amp;&amp; isset($this-&gt;aFieldnames[1])) { $sIndexKey = $this-&gt;aFieldnames[0]; $sIndexValue = $this-&gt;aFieldnames[1]; $aReturn = array(); foreach($this-&gt;aResultSet as $aResultRow) { $aReturn[$aResultRow[$sIndexKey]] = $aResultRow[$sIndexValue]; } return $aReturn; } return array(); } /** * @return array */ public function getAll() { $this-&gt;_execute(func_get_args()); $this-&gt;_fetchAll(); return $this-&gt;aResultSet; } /**#@-*/ /** * @return false|int */ public function numRows() { return $this-&gt;iNumRows; } /** * @return int */ public function affectedRows() { return $this-&gt;oStatement-&gt;affected_rows; } /** * @return int */ public function lastInsertId() { return $this-&gt;oStatement-&gt;insert_id; } public function getLastExecutedQuery() { $sReturn = $this-&gt;sQuery; if($this-&gt;aArgs) { $sReturn .= "; -- Argumente: ~".implode("~,~", $this-&gt;aArgs)."~"; } return $sReturn; } /** * @throws DbException * * @param array $aArgs */ private function _execute($aArgs) { $aArgs = $this-&gt;_parseFuncArgs($aArgs); $this-&gt;aArgs = $aArgs; $iArgs = count($aArgs); if($iArgs) { if($this-&gt;oStatement-&gt;param_count !== $iArgs ) { throw new DbException( "Inserting parameters failed: ".$this-&gt;oStatement-&gt;param_count. " Parameters expected but ".$iArgs." passed." ); } $aRefArgs = array(); foreach(array_keys($aArgs) as $mIndex) { $aRefArgs[$mIndex] = &amp;$aArgs[$mIndex]; } array_unshift($aRefArgs, str_repeat("s", $iArgs)); // Needs References call_user_func_array(array($this-&gt;oStatement, "bind_param"), $aRefArgs); } $bWorked = $this-&gt;oStatement-&gt;execute(); if($bWorked === false) { $sError = sprintf( "Query failed: %s (%s) Query was: '%s'", $this-&gt;oStatement-&gt;error, $this-&gt;oStatement-&gt;errno, $this-&gt;sQuery ); switch($this-&gt;oStatement-&gt;errno) { case 1062: throw new DbKeyViolationException($sError, $this-&gt;oStatement-&gt;errno); default: throw new DbException($sError, $this-&gt;oStatement-&gt;errno); } } $this-&gt;_prepareFetch(); } private function _prepareFetch() { if($this-&gt;bMetadata &amp;&amp; !$this-&gt;bPreparedFetch) { $oMeta = $this-&gt;oStatement-&gt;result_metadata(); if($oMeta === false) { $this-&gt;bMetadata = false; } else { $this-&gt;_prepareMetadata($oMeta); $this-&gt;aResultRow = array_fill(0, count($this-&gt;aFieldnames), null); // Ugly but 'bind_result' forces you to pass references $aRefs = array(); foreach ($this-&gt;aResultRow as $iIndex =&gt; &amp;$rmValue) { $aRefs[$iIndex] = &amp;$rmValue; } call_user_func_array(array($this-&gt;oStatement, "bind_result"), $this-&gt;aResultRow); $this-&gt;bPreparedFetch = true; } } } /** * @param mysqli_result $oMeta */ private function _prepareMetadata(mysqli_result $oMeta) { $aFields = $oMeta-&gt;fetch_fields(); foreach($aFields as $oField) { $this-&gt;aFieldnames[] = $oField-&gt;name; } } private function _fetchRow() { $this-&gt;_fetch(true); } private function _fetchAll() { $this-&gt;_fetch(false); } /* * @param bool $bOne One line ? */ private function _fetch($bOne) { $this-&gt;aResultSet = array(); if($bOne !== true) { $this-&gt;oStatement-&gt;store_result(); } while($this-&gt;oStatement-&gt;fetch()) { // Deref $aTmp = array(); foreach($this-&gt;aResultRow as $mValue) { $aTmp[] = $mValue; } $this-&gt;aResultSet[] = array_combine($this-&gt;aFieldnames, $aTmp); if($bOne === true) { break; } } $this-&gt;iNumRows = $this-&gt;oStatement-&gt;num_rows; $this-&gt;_done(); } private function _done() { $this-&gt;oStatement-&gt;free_result(); } /** * @param array $aArgs * @return array */ private function _parseFuncArgs($aArgs) { if(isset($aArgs[0]) &amp;&amp; is_array($aArgs[0])) { return $aArgs[0]; } return $aArgs; } } </code></pre> <p>The ugly bits (I think, that is why we are here I guess), are in <code>_execute</code> and <code>_prepareFetch</code> as the MySQLi API forced us to use references.</p> <p>The class takes for granted that the passed in MySQLi object is already connected to a database.</p> <p>If I missed something please let me know.</p>

146

<p>I want to have fast cache in which I want to keep all my nomenclature data. I don't want to go with Memcached because I have to do serialize/de-serialize on each object which is slow.</p> <p>So I choose to be less effective in memory and keep the cache in each server instance. I am sure I am doing it in the wrong way because the NoCache module - which skips my cache and hits the Rails cache is faster than mine.</p> <p>Here is how it is initialized</p> <pre><code>$cache = Cache.new </code></pre> <p>Here is the example usage</p> <pre><code>property_types = $cache['PropertyType'] </code></pre> <p>and here is the source</p> <pre><code>module DirectCache def init_cache end def reload_model(model_class) key = get_key(model_class) klass = key.constantize object = klass.scoped puts "Loading cache for #{key}..." if klass.respond_to?(:translates) and klass.translates? puts " Adding translation in the model for #{klass}" object = object.includes(:translations) self.storage[key] = object.send("all") end end def [] class_name_or_object puts "Hiting cache for #{class_name_or_object}" key = get_key(class_name_or_object) reload_model(class_name_or_object) if self.storage[key].blank? or self.storage[key].empty? raise "#{key} is missing in the cache #{@cache.keys.join ', '}" unless key? key self.storage[key] end def init_cache end end module NoCache def reload_model(model_class) key = get_key(model_class) self.storage[key] = key.constantize end def [] class_name_or_object key = get_key(class_name_or_object) raise "#{key} is missing in the cache #{@cache.keys.join ', '}" unless key? key klass = self.storage[key] object = klass.scoped if klass.respond_to?(:translates) and klass.translates? puts "Adding translation in the model for #{klass}" object = object.includes(:translations) end object.send("all") end def init_cache end end class Cache include DirectCache # include NoCache # include OpenStructCache @@models = [ PropertyFunction, PropertyCategoryLocation, ConstructionType, ....20 more .... ExposureType, ] cattr_reader :models def initialize @cache = {} begin init_cache rescue puts "missing tables" end end def storage @cache end # returns the the key - aways string def get_key class_name_or_record case class_name_or_record when Class key = class_name_or_record.to_s when String key = class_name_or_record else key = class_name_or_record.class.to_s end key end def key? class_name_or_object key = get_key(class_name_or_object) self.storage.keys.include? key end end </code></pre>

147

<p>I'm working on a personal project to keep different snippets/examples/small projects of mine organized. I want to make the most of my page width, so I decided to write a navigation menu that slides out. It works as expected, but the code is kinda big.</p> <p>I provided the HTML/CSS just in case that helps, but I'm really only looking for help with the JavaScript. I don't need anyone to rewrite the whole thing.</p> <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false"> <div class="snippet-code"> <pre class="snippet-code-js lang-js prettyprint-override"><code>$(document).ready(function() { $('#tab').click(function() { if($('#main').attr('class') != 'out') { $('#main').animate({ 'margin-left': '+=340px', }, 500, function() { $('#main').addClass('out'); }); } else { $('#main').animate({ 'margin-left': '-=340px', }, 500, function() { $('#main').removeClass('out'); }); } }); //does the same as above, but when I press ctrl + 1. from /http://www.scottklarr.com/topic/126/how-to-create-ctrl-key-shortcuts-in-javascript/ $(document).keyup(function (e) { if(e.which == 17) isCtrl=false; }).keydown(function (e) { if(e.which == 17) isCtrl=true; if(e.which == 97 &amp;&amp; isCtrl == true) { if($('#main').attr('class') != 'out') { $('#main').animate({ 'margin-left': '+=340px', }, 500, function() { $('#main').addClass('out'); }); } else { $('#main').animate({ 'margin-left': '-=340px', }, 500, function() { $('#main').removeClass('out'); }); } return false; } }); });</code></pre> <pre class="snippet-code-css lang-css prettyprint-override"><code>#sidebar { top: 0; left: 0; position: relative; float: left; } #main { width: 320px; padding: 10px; float: left; margin-left: -340px; } #tab { width: 30px; height: 120px; padding: 10px; float: left; } .clear { clear: both; }</code></pre> <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;div id="sidebar"&gt; &lt;div id="main"&gt;&lt;/div&gt; &lt;div id="tab"&gt;&lt;/div&gt; &lt;br class="clear"&gt; &lt;/div&gt;</code></pre> </div> </div> </p>

148

<p>I have a class with quite a few attributes, most of which are known when I create an instance of the object. So I pass all the values in the constructor:</p> <pre><code>$op = new OpenIdProvider($imgPath . $name . $ext, 'openid_highlight', 0, 0, 108, 68, 6, $info[0], $info[1], $name); </code></pre> <p>I'm finding that having this many parameters makes it confusing both when writing and reading the code, as it's not easy to determine which attribute each value corresponds to. Also, this has a bit of a code smell to it - seems like there should be a better way. Any suggestions?</p>

150

<p>I installed settingslogic and in the configuration file I put the regex for the email as follows:</p> <pre><code>#config/settings.yml defaults: &amp;defaults email_regex: /^([\w\.%\+\-]+)@([\w\-]+\.)+([\w]{2,})$/i development: &lt;&lt;: *defaults # neat_setting: 800 test: &lt;&lt;: *defaults production: &lt;&lt;: *defaults </code></pre> <p>That I load in devise configuration in this way:</p> <pre><code>#config/initializers/devise.rb # Regex to use to validate the email address # config.email_regexp = /^([\w\.%\+\-]+)@([\w\-]+\.)+([\w]{2,})$/i config.email_regexp = eval Settings.email_regex </code></pre> <p>It works, but what do you think about that <code>eval</code>? Is it the correct way to convert a string to a regex?</p>

159

<p>Is this code good enough, or is it stinky? </p> <pre><code>using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.IO; namespace DotNetLegends { public class LogParser { /// &lt;summary&gt; /// Returns a populated Game objects that has a list of players and other information. /// &lt;/summary&gt; /// &lt;param name="pathToLog"&gt;Path to the .log file.&lt;/param&gt; /// &lt;returns&gt;A Game object.&lt;/returns&gt; public Game Parse(string pathToLog) { Game game = new Game(); //On actual deployment of this code, I will use the pathToLog parameter. StreamReader reader = new StreamReader(@"D:\Games\Riot Games\League of Legends\air\logs\LolClient.20110121.213758.log"); var content = reader.ReadToEnd(); game.Id = GetGameID(content); game.Length = GetGameLength(content); game.Map = GetGameMap(content); game.MaximumPlayers = GetGameMaximumPlayers(content); game.Date = GetGameDate(content); return game; } internal string GetGameID(string content) { var location = content.IndexOf("gameId"); var gameID = content.Substring(location + 8, 10); gameID = gameID.Trim(); return gameID; } internal string GetGameLength(string content) { var location = content.IndexOf("gameLength"); var gamelength = content.Substring(location + 13, 6); gamelength = gamelength.Trim(); var time = Convert.ToInt32(gamelength) / 60; return time.ToString(); } internal string GetGameMap(string content) { var location = content.IndexOf("mapId"); var gameMap = content.Substring(location + 8, 1); switch (gameMap) { case "2": return "Summoner's Rift"; default: return "nul"; } } internal string GetGameMaximumPlayers(string content) { var location = content.IndexOf("maxNumPlayers"); var maxPlayers = content.Substring(location + 16, 2); maxPlayers = maxPlayers.Trim(); return maxPlayers; } internal string GetGameDate(string content) { var location = content.IndexOf("creationTime"); var creationDate = content.Substring(location + 14, 34); creationDate = creationDate.Trim(); return creationDate; } } } </code></pre>

164

<p><strong>Note:</strong> This file is out of my hands. I cannot change the format or type of file I have to parse.</p> <p>Here is some sample data that I'm trying to parse. This is information for just <strong>one</strong> player:</p> <pre><code>[0] (com.riotgames.platform.gameclient.domain::PlayerParticipantStatsSummary)#8 _profileIconId = 4 elo = 0 eloChange = 0 gameId = 82736631 gameItems = (null) inChat = false leaver = false leaves = 1 level = 5 losses = 2 profileIconId = 4 skinName = "Vladimir" statistics = (mx.collections::ArrayCollection)#9 filterFunction = (null) length = 26 list = (mx.collections::ArrayList)#10 length = 26 source = (Array)#11 [0] (com.riotgames.platform.gameclient.domain::RawStatDTO)#12 displayName = (null) statTypeName = "PHYSICAL_DAMAGE_TAKEN" value = 11156 [1] (com.riotgames.platform.gameclient.domain::RawStatDTO)#13 displayName = (null) statTypeName = "TOTAL_DAMAGE_TAKEN" value = 20653 [2] (com.riotgames.platform.gameclient.domain::RawStatDTO)#14 displayName = (null) statTypeName = "ITEM2" value = 3158 [3] (com.riotgames.platform.gameclient.domain::RawStatDTO)#15 displayName = (null) statTypeName = "ITEM4" value = 3089 [4] (com.riotgames.platform.gameclient.domain::RawStatDTO)#16 displayName = (null) statTypeName = "WIN" value = 1 [5] (com.riotgames.platform.gameclient.domain::RawStatDTO)#17 displayName = (null) statTypeName = "PHYSICAL_DAMAGE_DEALT_PLAYER" value = 18413 [6] (com.riotgames.platform.gameclient.domain::RawStatDTO)#18 displayName = (null) statTypeName = "TOTAL_HEAL" value = 16877 [7] (com.riotgames.platform.gameclient.domain::RawStatDTO)#19 displayName = (null) statTypeName = "ITEM0" value = 3083 [8] (com.riotgames.platform.gameclient.domain::RawStatDTO)#20 displayName = (null) statTypeName = "LARGEST_CRITICAL_STRIKE" value = 173 [9] (com.riotgames.platform.gameclient.domain::RawStatDTO)#21 displayName = (null) statTypeName = "ITEM3" value = 3116 [10] (com.riotgames.platform.gameclient.domain::RawStatDTO)#22 displayName = (null) statTypeName = "ITEM1" value = 0 [11] (com.riotgames.platform.gameclient.domain::RawStatDTO)#23 displayName = (null) statTypeName = "GOLD_EARNED" value = 11123 [12] (com.riotgames.platform.gameclient.domain::RawStatDTO)#24 displayName = (null) statTypeName = "ASSISTS" value = 8 [13] (com.riotgames.platform.gameclient.domain::RawStatDTO)#25 displayName = (null) statTypeName = "LARGEST_MULTI_KILL" value = 2 [14] (com.riotgames.platform.gameclient.domain::RawStatDTO)#26 displayName = (null) statTypeName = "MAGIC_DAMAGE_DEALT_PLAYER" value = 103124 [15] (com.riotgames.platform.gameclient.domain::RawStatDTO)#27 displayName = (null) statTypeName = "BARRACKS_KILLED" value = 0 [16] (com.riotgames.platform.gameclient.domain::RawStatDTO)#28 displayName = (null) statTypeName = "LARGEST_KILLING_SPREE" value = 5 [17] (com.riotgames.platform.gameclient.domain::RawStatDTO)#29 displayName = (null) statTypeName = "ITEM5" value = 0 [18] (com.riotgames.platform.gameclient.domain::RawStatDTO)#30 displayName = (null) statTypeName = "MINIONS_KILLED" value = 176 [19] (com.riotgames.platform.gameclient.domain::RawStatDTO)#31 displayName = (null) statTypeName = "CHAMPIONS_KILLED" value = 11 [20] (com.riotgames.platform.gameclient.domain::RawStatDTO)#32 displayName = (null) statTypeName = "MAGIC_DAMAGE_TAKEN" value = 8581 [21] (com.riotgames.platform.gameclient.domain::RawStatDTO)#33 displayName = (null) statTypeName = "NEUTRAL_MINIONS_KILLED" value = 12 [22] (com.riotgames.platform.gameclient.domain::RawStatDTO)#34 displayName = (null) statTypeName = "TOTAL_TIME_SPENT_DEAD" value = 189 [23] (com.riotgames.platform.gameclient.domain::RawStatDTO)#35 displayName = (null) statTypeName = "TURRETS_KILLED" value = 0 [24] (com.riotgames.platform.gameclient.domain::RawStatDTO)#36 displayName = (null) statTypeName = "NUM_DEATHS" value = 5 [25] (com.riotgames.platform.gameclient.domain::RawStatDTO)#37 displayName = (null) statTypeName = "TOTAL_DAMAGE_DEALT" value = 121538 uid = "B6F2F234-2E37-D979-E896-AA7614FCE9CB" sort = (null) source = (Array)#11 summonerName = "WeFearTheSun" teamId = 100 userId = 21672484 wins = 6 </code></pre> <p>Now there are ten players in a game, meaning ten of that snippet above, each one with an increasing counter, [1],[2],[3], and so on.</p> <p>As you can see <strong>inside</strong> of this data there are further numbers, ie. another <code>[0]</code>.</p> <p>If the numbers were unique I could just parse the <code>[0]</code>, then the <code>[1]</code>, then the <code>[2]</code>, etc.</p> <p>Right now I'm parsing the files like so:</p> <pre><code>private IEnumerable&lt;Player&gt; GetGamePlayers(string content) { List&lt;Player&gt; Players = new List&lt;Player&gt;(); var location = content.IndexOf("com.riotgames.platform.gameclient.domain::EndOfGameStats"); var cutContent = content.Substring(location, 65000); var playerOneLocation = cutContent.IndexOf("[0]"); //var playerOneContent = cutContent.Substring(playerOneLocation, 6231); var playerOneContent = cutContent.Substring(playerOneLocation, 6255); Players.Add(ParsePlayer(playerOneContent)); cutContent = cutContent.Substring(playerOneLocation + 6229, cutContent.Length - playerOneLocation - 6229); var playerTwoLocation = cutContent.IndexOf("[1]"); var playerTwoContent = cutContent.Substring(playerTwoLocation, 6255); Players.Add(ParsePlayer(playerTwoContent)); cutContent = cutContent.Substring(playerTwoLocation + 6229, cutContent.Length - playerTwoLocation - 6229); var playerThreeLocation = cutContent.IndexOf("[2]"); var playerThreeContent = cutContent.Substring(playerThreeLocation, 6255); Players.Add(ParsePlayer(playerThreeContent)); cutContent = cutContent.Substring(playerThreeLocation + 6229, cutContent.Length - playerThreeLocation - 6229); var playerFourLocation = cutContent.IndexOf("[3]"); var playerFourContent = cutContent.Substring(playerFourLocation, 6255); Players.Add(ParsePlayer(playerFourContent)); cutContent = cutContent.Substring(playerFourLocation + 6229, cutContent.Length - playerFourLocation - 6229); var playerFiveLocation = cutContent.IndexOf("[4]"); var playerFiveContent = cutContent.Substring(playerFiveLocation, 6255); Players.Add(ParsePlayer(playerFiveContent)); location = cutContent.IndexOf("teamPlayerParticipantStats"); cutContent = cutContent.Substring(location, 32000); var playerSixLocation = cutContent.IndexOf("[0]"); var playerSixContent = cutContent.Substring(playerSixLocation, 6255); Players.Add(ParsePlayer(playerSixContent)); cutContent = cutContent.Substring(playerSixLocation + 6229, cutContent.Length - playerSixLocation - 6229); var playerSevenLocation = cutContent.IndexOf("[1]"); var playerSevenContent = cutContent.Substring(playerSevenLocation, 6255); Players.Add(ParsePlayer(playerSevenContent)); cutContent = cutContent.Substring(playerSevenLocation + 6229, cutContent.Length - playerSevenLocation - 6229); var playerEightLocation = cutContent.IndexOf("[2]"); var playerEightContent = cutContent.Substring(playerEightLocation, 6255); Players.Add(ParsePlayer(playerEightContent)); cutContent = cutContent.Substring(playerEightLocation + 6229, cutContent.Length - playerEightLocation - 6229); var playerNineLocation = cutContent.IndexOf("[3]"); var playerNineContent = cutContent.Substring(playerNineLocation, 6255); Players.Add(ParsePlayer(playerNineContent)); cutContent = cutContent.Substring(playerNineLocation + 6229, cutContent.Length - playerNineLocation - 6229); var playerTenLocation = cutContent.IndexOf("[4]"); var playerTenContent = cutContent.Substring(playerTenLocation, 6255); Players.Add(ParsePlayer(playerTenContent)); return Players; } </code></pre> <p>I can tell the code is horrible, and there is a lot of room for improvement. How would I divide the huge content into single blocks for each individual player?</p> <p>I need to get the string content:</p> <pre><code>[0] (com.riotgames.platform.gameclient.domain::PlayerParticipantStatsSummary)#8 to [1] (com.riotgames.platform.gameclient.domain::PlayerParticipantStatsSummary)#8 then: [1] (com.riotgames.platform.gameclient.domain::PlayerParticipantStatsSummary)#8 to [2] (com.riotgames.platform.gameclient.domain::PlayerParticipantStatsSummary)#8 </code></pre>

172

<p>The code below is a plugin I wrote for <code>Ext.grid.GridPanel</code>, which basically allows you to have a bit more control over how rows are striped in the grid. By default you can only have every other row in alternate colour. With this plugin you an have for example 5 in basic color, 5 in alternate and so on.</p> <p>What bothers me about it, is that it basically is 100+ lines copied from <code>Ext.grid.GridView</code> with no more than 10 lines of my modifications. I would love to know if there's a way to do it in a more elegant way.</p> <p>My second concern is with that it's a plugin for <code>Ext.grid.GridPanel</code>, but it actually modifies the underlying <code>Ext.grid.GridView</code>. As far as I know, there is no way to attach a plugin to a <code>GridView</code> with current framework architecture, but perhaps you DO know the way.</p> <p>Legal stuff: The code is largely based on ExtJS source code, and as such it's released under <a href="http://www.gnu.org/copyleft/gpl.html">GNU GPL license v3 license</a></p> <pre><code>MyNamespace.grid.plugins.RowStriper = Ext.extend(Object, { constructor : function(config) { config = config || {}; Ext.apply(this, config); }, init : function(parent) { if (parent instanceof Ext.grid.GridPanel) { this.parent = parent; this.parent.stripeInterval = this.stripeInterval; parent.on('destroy', this.onDestroy, this); Ext.apply(parent.getView(), this.parentViewOverrides); } }, onDestroy : Ext.emptyFn, parentViewOverrides : { doRender : function(columns, records, store, startRow, colCount, stripe) { var templates = this.templates, cellTemplate = templates.cell, rowTemplate = templates.row, last = colCount - 1; var tstyle = 'width:' + this.getTotalWidth() + ';'; // buffers var rowBuffer = [], colBuffer = [], rowParams = {tstyle: tstyle}, meta = {}, column, record; //build up each row's HTML for (var j = 0, len = records.length; j &lt; len; j++) { record = records[j]; colBuffer = []; var rowIndex = j + startRow; //build up each column's HTML for (var i = 0; i &lt; colCount; i++) { column = columns[i]; meta.id = column.id; meta.css = i === 0 ? 'x-grid3-cell-first ' : (i == last ? 'x-grid3-cell-last ' : ''); meta.attr = meta.cellAttr = ''; meta.style = column.style; meta.value = column.renderer.call(column.scope, record.data[column.name], meta, record, rowIndex, i, store); if (Ext.isEmpty(meta.value)) { meta.value = '&amp;#160;'; } if (this.markDirty &amp;&amp; record.dirty &amp;&amp; Ext.isDefined(record.modified[column.name])) { meta.css += ' x-grid3-dirty-cell'; } colBuffer[colBuffer.length] = cellTemplate.apply(meta); } //set up row striping and row dirtiness CSS classes var alt = []; if (stripe &amp;&amp; (rowIndex % (this.grid.stripeInterval * 2)) &gt; (this.grid.stripeInterval - 1)) { alt[0] = 'x-grid3-row-alt'; } if (record.dirty) { alt[1] = ' x-grid3-dirty-row'; } rowParams.cols = colCount; if (this.getRowClass) { alt[2] = this.getRowClass(record, rowIndex, rowParams, store); } rowParams.alt = alt.join(' '); rowParams.cells = colBuffer.join(''); rowBuffer[rowBuffer.length] = rowTemplate.apply(rowParams); } return rowBuffer.join(''); }, processRows : function(startRow, skipStripe) { if (!this.ds || this.ds.getCount() &lt; 1) { return; } var rows = this.getRows(), len = rows.length, i, r; skipStripe = skipStripe || !this.grid.stripeRows; var stripeInterval = this.grid.stripeInterval || 1; startRow = startRow || 0; for (i = 0; i&lt;len; i++) { r = rows[i]; if (r) { r.rowIndex = i; if (!skipStripe) { r.className = r.className.replace(this.rowClsRe, ' '); if ((i % (stripeInterval * 2)) &gt; (stripeInterval - 1)){ r.className += ' x-grid3-row-alt'; } } } } // add first/last-row classes if (startRow === 0) { Ext.fly(rows[0]).addClass(this.firstRowCls); } Ext.fly(rows[rows.length - 1]).addClass(this.lastRowCls); } } }); </code></pre>

174

<p>Here's a class I'm designing:</p> <pre><code>using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Data; using System.Data.SqlClient; namespace Artworking.classes { // A group permission level public class PermissionGroup { public int ID; // Unique ID for this group public bool hasFullControl; // Does this group have complete control public user creator; // Who created this group public string groupName; // Reference name for group // Constructor for when a permission group ID is passed public PermissionGroup(SqlConnection cn, int ID) { using (SqlCommand cmd = new SqlCommand("SELECT creatorUserID, group_name, fullControl FROM tblATPermissionGroups WHERE ID = " + ID, cn)) { SqlDataReader rdr = cmd.ExecuteReader(); if (rdr.Read()) { this.creator.ID = int.Parse(rdr["creatorUserID"].ToString()); this.groupName = rdr["group_name"].ToString(); this.hasFullControl = bool.Parse(rdr["fullControl"].ToString()); } rdr.Close(); } } } } </code></pre> <p>Am I on the right track? Please note I'm not using the built in authentication as it needs to be backwards compatible for an old system. What I'm just checking is that I'm handling these classes properly and loading the data in correctly etc. As I understand it I'm meant to put my SQL commands in the classes and away from the actual pages right?</p>

177

<p>In <a href="https://codereview.stackexchange.com/questions/9/how-to-improve-very-loopy-method">this question</a> I answered with this Linq. While it does what I was looking for, I am not sure how easy the linq queries are for others to follow. So I am looking for feedback on formating, what comments would be helpful and other alternative approaches to moving through the children records.</p> <pre><code> private void UpdateGridFromSourceHierarchy(int depth, IEnumerable&lt;SourceFile&gt; list) { //Get the initial set of sourcefiles var sourceFiles = list .SelectMany(current =&gt; current.getInvocations() .Select(invocation =&gt; new {current = (SourceFile) null, invocation})) .ToList() //This ensures that getInvocations is only called once for each sourcefile .GroupBy(x =&gt; x.current, x =&gt; x.invocation); for (var currentDepth = 0; currentDepth &lt;= depth; currentDepth++) { foreach (var currentGroup in sourceFiles) { int sourceFileCount = currentGroup.Count(); int counter = 0; foreach (var invocation in currentGroup) { /* * Generalized grid code goes here * In my code it was a call to: * UpdateGridPosition(currentGroup,invocation,counter); */ counter++; } } //Select the current sub source files sourceFiles = sourceFiles.SelectMany(current =&gt; current.Select(invocation =&gt; invocation)) //Get all of the invocations paired with the new current level of source files .SelectMany(newCurrent =&gt; newCurrent.getInvocations() .Select(invocation =&gt; new { newCurrent, invocation })) //Group them so that we can loop through each set of invocations seperately .ToList().GroupBy(x =&gt; x.newCurrent, x =&gt; x.invocation); } } </code></pre>

182

<p>This is performance critical. I measured and determined that using the <code>sqrt</code> is faster then using the <code>cos</code> method.</p> <p>I am aware that this code only works for some points, so that is not an issue.</p> <p><code>Point</code> is <code>System.Drawing.Point</code>. <code>_offset</code> is also of type <code>Point</code>.</p> <p>I assumed, and the profiler seemed to confirm, that the <code>try</code>/<code>catch</code> will not slow down the code unless an exception occurs. Please correct me if that is wrong.</p> <pre><code>/// &lt;summary&gt; /// Convert from polar coordinates to rectangular coordinates. /// Only works for points to the left of the origin. /// &lt;/summary&gt; /// &lt;param name="radius"&gt;The radius of the point in pixels.&lt;/param&gt; /// &lt;param name="theta"&gt;The angle of the point in radians.&lt;/param&gt; /// &lt;returns&gt;The point in rectangular coordinates.&lt;/returns&gt; internal Point PolarToRectangular( double radius, double theta) { try { double sin = Math.Sin(theta); // This is faster then: // double cos = Math.Cos(theta); double cos = -Math.Sqrt(1 - (sin * sin)); Int32 x = _offset.X + (Int32)Math.Round(radius * cos); Int32 y = _offset.Y + (Int32)Math.Round(radius * sin); return new Point(x, y); } catch (OverflowException ex) { ex.Data.Add("Screen polar Radius", radius); ex.Data.Add("Screen polar Theta", theta); throw; } } </code></pre>

183

<p>I am unsure if my use of <code>Monitor.Wait</code> and <code>Monitor.Pulse</code> is correct. It seems to work alright, but there is a nagging doubt I am doing something wrong.</p> <p>Am I dealing with a timeout OK, or is there a better way to do it?</p> <p>All examples I have seen use <code>Monitor.Wait</code> with a <code>while</code> loop, and not with an <code>if</code> to re-check the blocking condition after <code>Pulse</code>, but I need to determine if a timeout occurred.</p> <p><code>_cmdDispatcher.EnqueueCommand(cmd)</code> sends a command to the device, and it responds with an event that executes the <code>CommResponseReceived</code> method on another thread.</p> <pre><code>private readonly object _connectLock = new object(); public bool Connect() { if (this._connected) throw new InvalidOperationException("Plc is already connected."); ICommand cmd = new Command(MessageIdentifier.Name); try { if (this._channel.Open() &amp;&amp; !this._connected) { // Wait for communications to be fully established or timeout before continuing. lock (this._connectLock) { this._cmdDispatcher.EnqueueCommand(cmd); if (!this._connectSignal) { if (Monitor.Wait(this._connectLock, this._timeout)) { this._connected = true; this._connectSignal = false; Debug.WriteLine("Connection succeeded."); } else { //TODO Log timeout. Debug.WriteLine("Connection timed out."); } } } if (this._connected) this.OnConnectionChangedEvent(ConnectionStatus.Connected); } } catch (Exception ex) { //TODO Log errors. Debug.WriteLine("Connection failed."); } return this._connected; } </code></pre> <p>Executed in another thread when the device responds:</p> <pre><code>private void CommResponseReceived(object sender, CommsResponseEventArgs e) { // // Signal that communications are successfully established. lock (this._connectLock) { this._connectSignal = true; Monitor.Pulse(this._connectLock); } } </code></pre>

185

<p>Imagine that I need a color palette for my Winforms application to have a consistent look.</p> <p>What I did was create a static helper class and helper methods that I can call from anywhere in my code, and invoke what I need from the <code>App.settings</code> file.</p> <p>Here for example, I am getting the school name from the <code>App.config</code> file, so I can sell this application to other schools with minimal changes on my part.</p> <pre class="lang-xml prettyprint-override"><code>&lt;?xml version="1.0" encoding="utf-8" ?&gt; &lt;configuration&gt; &lt;appSettings&gt; &lt;add key="schoolName" value="Uboldi"/&gt; &lt;/appSettings&gt; &lt;/configuration&gt; </code></pre> <pre class="lang-cs prettyprint-override"><code>using System; using System.Collections.Generic; using System.Linq; using System.Text; using System.Configuration; namespace Uboldi.Helpers { public static class CustomizationHelper { public static string GetSchoolName() { return ConfigurationManager.AppSettings["schoolName"]; } } } </code></pre> <p>Usage:</p> <pre><code>using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using Uboldi.Helpers; namespace Uboldi { public partial class MainForm : Form { public MainForm() { InitializeComponent(); LoadFormTitle(); } private void LoadFormTitle() { var schoolName = CustomizationHelper.GetSchoolName(); this.Text = String.Format("Sistema {0} - Pagina Principal", schoolName); } } } </code></pre> <p>Are there any glaring mistakes I'm making by choosing this type of architecture?</p>

186

<p>I'm learning Django as I go. I know this model is missing user authentication, registration, comments/comment threading, and voting. But this is my starting code for my model. What are some of the things I can improve on, modify, rewrite, etc?</p> <pre><code>from django.contrib.auth.models import User from django.db import models from django.contrib import admin from django.template.defaultfilters import escape from django.utils.translation import ugettext as _ from django.utils.encoding import force_unicode from django.http import HttpResponse, HttpResponseRedirect from django.core.urlresolvers import reverse class DateTime(models.Model): datetime = models.DateTimeField(auto_now_add=True) def __unicode__(self): return unicode(self.datetime.strftime("%b %d, %Y, %I:%M %p")) class Country(models.Model): country = models.CharField(max_length=50) def __unicode__(self): return unicode(self.country) class Artist(models.Model): artist = models.CharField(max_length=50) country = models.ForeignKey(Country, blank=True, null=True) user = models.ForeignKey(User, blank=True, null=True) created = models.ForeignKey(DateTime) notes = models.TextField() def __unicode__(self): return artist class Song(models.Model): name = models.CharField(max_length=200) artist = models.ForeignKey(Artist, blank=True, null=True) # language = models.ForeignKey(Country, blank=True, null=True) user = models.ForeignKey(User, blank=True, null=True) created = models.ForeignKey(DateTime) notes = models.TextField() def __unicode__(self): return song class FileType(models.Model): file_type = models.CharField(max_length=3) description = models.TextField() user = models.ForeignKey(User, blank=True, null=True) created = models.ForeignKey(DateTime) notes = models.TextField() def __unicode__(self): return file_type class Level(models.Model): level = models.CharField(max_length=3) description = models.TextField() user = models.ForeignKey(User, blank=True, null=True) created = models.ForeignKey(DateTime) notes = models.TextField() def __unicode__(self): return level class MusicSheet(models.Model): version = models.CharField(max_length=2) song = models.ForeignKey(Song, blank=True, null=True) artist = models.ForeignKey(Artist, blank=True, null=True) file_type = models.ForeignKey(FileType, blank=True, null=True) level = models.ForeignKey(Level, blank=True, null=True) user = models.ForeignKey(User, blank=True, null=True) created = models.ForeignKey(DateTime) text = models.TextField() notes = models.TextField() #include votes #include comments #include registration code ######################################################################################################################## ######################################## ADMIN STUFF ################################################################### ######################################################################################################################## class MusicSheetAdmin(admin.ModelAdmin): list_display = ["version", "song", "artist", "file_type", "level", "user" , "created", "text", "notes"] search_fields = ["version"] class MusicSheetInline(admin.TabularInline): model = MusicSheet class DateAdmin(admin.ModelAdmin): list_display = ["datetime"] inlines = [MusicSheetInline] def response_add(self, request, obj, post_url_continue='../%s/'): """ Determines the HttpResponse for the add_view stage. """ opts = obj._meta pk_value = obj._get_pk_val() msg = "Song(s) were added successfully." # Here, we distinguish between different save types by checking for # the presence of keys in request.POST. if request.POST.has_key("_continue"): self.message_user(request, msg + ' ' + _("You may edit it again below.")) if request.POST.has_key("_popup"): post_url_continue += "?_popup=1" return HttpResponseRedirect(post_url_continue % pk_value) if request.POST.has_key("_popup"): return HttpResponse( '&lt;script type="text/javascript"&gt;opener.dismissAddAnotherPopup(window, "%s", "%s");' '&lt;/script&gt;' % (escape(pk_value), escape(obj))) elif request.POST.has_key("_addanother"): self.message_user(request, msg + ' ' + (_("You may add another %s below.") % force_unicode(opts.verbose_name))) return HttpResponseRedirect(request.path) else: self.message_user(request, msg) for music_sheet in MusicSheet.objects.filter(created=obj): if not music_sheet.user: music_sheet.user = request.user music_sheet.save() return HttpResponseRedirect(reverse("admin:musicsheet_musicsheet_changelist")) class CountryAdmin(admin.ModelAdmin): list_display = ["country"] search_fields = ["country"] class CountryInline(admin.TabularInline): model = MusicSheet class SongAdmin(admin.ModelAdmin): list_display = ["name", "artist", "user", "created", "notes"] search_fields = ["name", "artist"] class SongInline(admin.TabularInline): model = MusicSheet class ArtistAdmin(admin.ModelAdmin): list_display = ["artist", "country", "user", "created", "notes"] search_fields = ["artist", "country"] class ArtistInline(admin.TabularInline): model = MusicSheet class FileTypeAdmin(admin.ModelAdmin): list_display = ["file_type", "description", "user", "created", "notes"] search_fields = ["file_type"] class FileTypeInline(admin.StackedInline): model = MusicSheet class LevelAdmin(admin.ModelAdmin): list_display = ["level", "description", "user", "created", "notes"] search_fields = ["level"] class LevelInline(admin.StackedInline): model = MusicSheet admin.site.register(MusicSheet, MusicSheetAdmin) admin.site.register(Country, CountryAdmin) admin.site.register(Song, SongAdmin) admin.site.register(Artist, ArtistAdmin) admin.site.register(FileType, FileTypeAdmin) admin.site.register(Level, LevelAdmin) admin.site.register(DateTime, DateAdmin) </code></pre>

187

<p>I've recently assembled some jQuery that allows a user to build out a bulleted list in MS Word with hyperlinks and turn that into a HTML unordered list. Ideas for uses are website menu systems where the user may not have a clue about HTML. You can also extend this with jQuery UI plugins for effects. Looking for edge cases.</p> <pre><code>/* The following will read in a bullet list from in a MS Word XML file and turn it into a unordered list with hyperlinks. Perhaps to use as a menu. */ $.ajax({ type: "GET", async: false, url: "Menu.xml", dataType: "xml", success:function(results){ var currentDepth = 0; $("#menu").append('&lt;ul class="menuLvl'+currentDepth+'"&gt;&lt;/ul&gt;'); $(results).find("[nodeName=w:p]").each(function(){ if($(this).find("[nodeName=w:pStyle]").attr('w:val') == 'ListParagraph'){ var liValue = $(this).find("[nodeName=w:t]").text(); var hyper = $(this).find("[nodeName=w:hyperlink]").attr('r:id'); var placeAtDepth = parseInt($(this).find("[nodeName=w:ilvl]").attr('w:val'), 10); if(placeAtDepth &gt; currentDepth){ $(".menuLvl"+ currentDepth).append('&lt;ul class="menuLvl'+ placeAtDepth +'"&gt;'); } currentDepth = placeAtDepth; //Determine if we have an hyperlink if(hyper != null){ var link = $(results).find('Relationship[Id='+hyper+']').attr('Target'); liValue = '&lt;a href="'+ link +'"&gt;'+ liValue +'&lt;/a&gt;'; } $(".menuLvl"+currentDepth).last().append('&lt;li&gt;'+ liValue +'&lt;/li&gt;'); } }); } }); </code></pre>

190

<p>I'm looking into Administration Elevation and I've come up with a solution that seems like it's perfectly sane, but I'm still in the dark about the professional methods to accomplish this.</p> <p>Is there a better way to do this or is this fine? </p> <pre><code>using System; using System.Diagnostics; using System.Security.Principal; using System.Windows.Forms; namespace MyVendor.Installation { static class Program { [STAThread] static void Main() { Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); if (!IsRunAsAdmin()) { Elevate(); Application.Exit(); } else { try { Installer InstallerForm = new Installer(); Application.Run(InstallerForm); } catch (Exception e) { //Display Exception message! Logging.Log.Error("Unrecoverable exception:", e); Application.Exit(); } } } internal static bool IsRunAsAdmin() { var Principle = new WindowsPrincipal(WindowsIdentity.GetCurrent()); return Principle.IsInRole(WindowsBuiltInRole.Administrator); } private static bool Elevate() { var SelfProc = new ProcessStartInfo { UseShellExecute = true, WorkingDirectory = Environment.CurrentDirectory, FileName = Application.ExecutablePath, Verb = "runas" }; try { Process.Start(SelfProc); return true; } catch { Logging.Log.Error("Unable to elevate!"); return false; } } } } </code></pre>

197

<p>I have a database class that in <code>__construct()</code> initialize a PDO connection and insert the instance into a $db private var. Now i'm working on a method that can be used to query in this way:</p> <pre><code>$db = new db; $db-&gt;query(array( 'select' =&gt; 1, 'from' =&gt; 'table', 'where' =&gt; array('id' =&gt; 1, 'name' =&gt; 'charlie'), 'limit' =&gt; array(1, 5) )); </code></pre> <p>I did something that works pretty nicely long time ago while PDO was something unknown, but i was wondering:</p> <ol> <li>How could i improve this code a bit</li> <li>How can i end it? I mean how to use the PDO then to submit the query?</li> </ol> <p>Here's the method <code>query()</code>:</p> <pre><code># Defining the type if (isset($array['select'])) { $type = 'SELECT'; $type_value = (is_int($array['select'])) ? '*' : $array['select']; } if (isset($array['update'])) { $type = 'UPDATE'; $type_value = $array['update']; } if (isset($array['delete'])) { $type = 'DELETE FROM'; $type_value = $array['delete']; } if (isset($array['insert'])) { $type = 'INSERT INTO'; $type_value = $array['insert']; } if (!isset($type)) { trigger_error("Database, 'type' not selected."); } // Error # From if (isset($array['from'])) { $from = 'FROM'; $from_value = mysql_real_escape_string($array['from']); // table cannot be pdoed } # Where if (isset($array['where'])) { if (!is_array($array['where'])) { trigger_error("Database, 'where' key must be array."); } $where = 'WHERE'; $where_value = $array['where']; # Fixing the AND problem if (count($array['where']) &gt; 1) { $list = $where_value; foreach ($list as $a =&gt; $b) { $w[] = "{$a} = {$b}"; } $and = implode(' AND ', $w); $where_value = $and; } } # Limit if (isset($array['limit'])) { if (!is_array($array['limit'])) { trigger_error("Database, 'limit' key must be array."); } if (count($array['limit']) != 2) { trigger_error("Database, 'limit' array must be two-keys-long"); } $limit_first = $array['limit'][0]; $limit_second = $array['limit'][1]; $limit = 'LIMIT'; $limit_value = "{$limit_first}, {$limit_second}"; } # Set if (isset($array['set'])) { if (!is_array($array['set'])) { trigger_error("Database, 'set' key must be array."); } $edits = $array['set']; foreach ($edits as $a =&gt; $b) { $e[] = "{$a} = {$b}"; } $set = 'SET'; $set_value = implode(',', $e); } $vals = array('from', 'from_value', 'set', 'set_value', 'where', 'where_value'); foreach ($vals as $v) { if (empty($$v)) { $$v = ''; } } $sql = " {$type} {$type_value} {$from} {$from_value} {$set} {$set_value} {$where} {$where_value} "; # Here there would be something like mysql_query($sql), but i'd like PDO! PDO get me hornier. </code></pre> <p>And now? How to bind parameters? Is that possible to work it out?</p>

200

<p>I found that in PHP (or I probably can't find it) a proper <code>is_numeric_array($array)</code> function is missing. So I created one. The problem is that I don't think it's great and I don't know how to improve it.</p> <p>Any suggestion?</p> <p><strong>My first function</strong></p> <pre><code>function is_numeric_array($array) { $i = 0; foreach ($array as $a =&gt; $b) { if (is_int($a)) { ++$i; } } if (count($array) === $i) { return true; } else { return false; } } is_numeric_array(array(0,0,0,0,0)); // true is_numeric_array(array('str' =&gt; 1, 'str2' =&gt; 2, 'str3' =&gt; 3)); // false </code></pre> <p><strong>Example</strong></p> <p>As asked, I provide an example on how this could be any useful.</p> <pre><code>function is_numeric_array($array) { # Code below } function someFunction($array) { if (is_numeric_array($array)) { $query = $array[0]; $param = $array[1]; $fetch = $array[2]; } else { $query = $array['query']; $param = $array['param']; $fetch = $array['fetch']; } # Do your sql/pdo stuff here } # This use is the same of ... someFunction(array( 'PDO SQL STATEMENT', array('param1' =&gt; 1, 'param2' =&gt; 2, 'param3' =&gt; 3), true )); # ... this one. someFunction(array( 'query' =&gt; 'PDO SQL STATEMENT', 'param' =&gt; array('param1' =&gt; 1, 'param2' =&gt; 2, 'param3' =&gt; 3), 'fetch' =&gt; true )); # To choose one form instead of the other is coder's decision # Also I know it is useless but I was just wondering why anybody actually looked forward this function </code></pre>

201

<p>I want to get empty string or the string value of the object</p> <p>Which code you will use and why?</p> <pre><code>value = object.to_s </code></pre> <p>or this</p> <pre><code>value = object.nil? ? "" : object </code></pre>

214

<p>This is part from an <a href="https://stackoverflow.com/questions/4706151/python-3-1-memory-error-during-sampling-of-a-large-list/4706317#4706317">answer to a Stack Overflow question</a>. The OP needed a way to perform calculations on samples from a population, but was hitting memory errors due to keeping samples in memory. </p> <p>The function is based on part of <a href="http://svn.python.org/view/python/trunk/Lib/random.py?view=markup#sample" rel="nofollow noreferrer">random.sample</a>, but only the code branch using a set is present.</p> <p>If we can tidy and comment this well enough, it might be worth publishing as a recipe at the <a href="http://code.activestate.com/recipes/" rel="nofollow noreferrer">Python Cookbook</a>.</p> <pre><code>import random def sampling_mean(population, k, times): # Part of this is lifted straight from random.py _int = int _random = random.random n = len(population) kf = float(k) result = [] if not 0 &lt;= k &lt;= n: raise ValueError, "sample larger than population" for t in xrange(times): selected = set() sum_ = 0 selected_add = selected.add for i in xrange(k): j = _int(_random() * n) while j in selected: j = _int(_random() * n) selected_add(j) sum_ += population[j] # Partial result we're interested in mean = sum_/kf result.append(mean) return result sampling_mean(x, 1000000, 100) </code></pre> <p>Maybe it'd be interesting to generalize it so you can pass a function that calculates the value you're interested in from the sample?</p>

217

<p>The requirements for this one were (<a href="https://stackoverflow.com/q/4630723/555569">original SO question</a>):</p> <ul> <li>Generate a random-ish sequence of items.</li> <li>Sequence should have each item N times.</li> <li>Sequence shouldn't have serial runs longer than a given number (longest below).</li> </ul> <p>The solution was actually drafted by another user, this is <a href="https://stackoverflow.com/questions/4630723/using-python-for-quasi-randomization/4630784#4630784">my implementation</a> (influenced by <a href="http://svn.python.org/view/python/trunk/Lib/random.py?view=markup#shuffle" rel="nofollow noreferrer">random.shuffle</a>).</p> <pre><code>from random import random from itertools import groupby # For testing the result try: xrange except: xrange = range def generate_quasirandom(values, n, longest=3, debug=False): # Sanity check if len(values) &lt; 2 or longest &lt; 1: raise ValueError # Create a list with n * [val] source = [] sourcelen = len(values) * n for val in values: source += [val] * n # For breaking runs serial = 0 latest = None for i in xrange(sourcelen): # Pick something from source[:i] j = int(random() * (sourcelen - i)) + i if source[j] == latest: serial += 1 if serial &gt;= longest: serial = 0 guard = 0 # We got a serial run, break it while source[j] == latest: j = int(random() * (sourcelen - i)) + i guard += 1 # We just hit an infinit loop: there is no way to avoid a serial run if guard &gt; 10: print("Unable to avoid serial run, disabling asserts.") debug = False break else: serial = 0 latest = source[j] # Move the picked value to source[i:] source[i], source[j] = source[j], source[i] # More sanity checks check_quasirandom(source, values, n, longest, debug) return source def check_quasirandom(shuffled, values, n, longest, debug): counts = [] # We skip the last entries because breaking runs in them get too hairy for val, count in groupby(shuffled): counts.append(len(list(count))) highest = max(counts) print('Longest run: %d\nMax run lenght:%d' % (highest, longest)) # Invariants assert len(shuffled) == len(values) * n for val in values: assert shuffled.count(val) == n if debug: # Only checked if we were able to avoid a sequential run &gt;= longest assert highest &lt;= longest for x in xrange(10, 1000): generate_quasirandom((0, 1, 2, 3), 1000, x//10, debug=True) </code></pre> <p>I'd like to receive any input you have on improving this code, from style to comments to tests and anything else you can think of. </p>

219

<p>I got this as an implementation of "get me the median of those values". But it sort of doesn't feel right (too long, too many branch points) so I thought I'll post it here to see what you think.</p> <pre><code>&lt;?php private function calculateMedian($aValues) { $aToCareAbout = array(); foreach ($aValues as $mValue) { if ($mValue &gt;= 0) { $aToCareAbout[] = $mValue; } } $iCount = count($aToCareAbout); sort($aToCareAbout, SORT_NUMERIC); if ($iCount &gt; 2) { if ($iCount % 2 == 0) { return ($aToCareAbout[floor($iCount / 2) - 1] + $aToCareAbout[floor($iCount / 2)]) / 2; } else { return $aToCareAbout[$iCount / 2]; } } elseif (isset($aToCareAbout[0])) { return $aToCareAbout[0]; } else { return 0; } } </code></pre>

220

<p>According to the Doctrine <a href="http://www.doctrine-project.org/projects/orm/1.2/docs/manual/working-with-models/en#fetching-objects" rel="noreferrer">docs</a>, you should use Array hydration rather than record hydration when retrieving data for read-only purposes.</p> <p>Unfortunately, this means I have to use array syntax (as opposed to object syntax) to reference the data.</p> <pre><code>$q = Doctrine_Query::create() -&gt;from('Post p') -&gt;leftJoin('p.PostComment pc') -&gt;leftJoin('pc.User u') -&gt;where('p.post_id = ?', $id); $p = $q-&gt;fetchOne(array(), Doctrine_Core::HYDRATE_ARRAY); ... foreach ($p['PostComment'] as $comment) { $this-&gt;Controls-&gt;Add(new CommentPanel($comment['text'], $comment['User']['nickname'], $comment['last_updated_ts'])); } </code></pre> <p>Maybe it's just me, but all of those string literals as array indexes are kinda scary. Does anyone have some ideas for cleaning this up?</p>

222

<p>I was trying to create a lock-free queue implementation in Java, mainly for personal learning. The queue should be a general one, allowing any number of readers and/or writers concurrently.</p> <p>Would you please review it, and suggest any improvements/issues you find?</p> <p>(<a href="https://stackoverflow.com/q/1634368/41283">Cross-post from StackOverflow</a>)</p> <pre><code>import java.util.concurrent.atomic.AtomicReference; public class LockFreeQueue&lt;T&gt; { private static class Node&lt;E&gt; { final E value; volatile Node&lt;E&gt; next; Node(E value) { this.value = value; } } private AtomicReference&lt;Node&lt;T&gt;&gt; head, tail; public LockFreeQueue() { // have both head and tail point to a dummy node Node&lt;T&gt; dummyNode = new Node&lt;T&gt;(null); head = new AtomicReference&lt;Node&lt;T&gt;&gt;(dummyNode); tail = new AtomicReference&lt;Node&lt;T&gt;&gt;(dummyNode); } /** * Puts an object at the end of the queue. */ public void putObject(T value) { Node&lt;T&gt; newNode = new Node&lt;T&gt;(value); Node&lt;T&gt; prevTailNode = tail.getAndSet(newNode); prevTailNode.next = newNode; } /** * Gets an object from the beginning of the queue. The object is removed * from the queue. If there are no objects in the queue, returns null. */ public T getObject() { Node&lt;T&gt; headNode, valueNode; // move head node to the next node using atomic semantics // as long as next node is not null do { headNode = head.get(); valueNode = headNode.next; // try until the whole loop executes pseudo-atomically // (i.e. unaffected by modifications done by other threads) } while (valueNode != null &amp;&amp; !head.compareAndSet(headNode, valueNode)); T value = (valueNode != null ? valueNode.value : null); // release the value pointed to by head, keeping the head node dummy if (valueNode != null) valueNode.value = null; return value; } } </code></pre>

224

<p>In our production code, we cannot use Boost or C++0x. Formatting strings using <code>sprintf</code> or <code>stringstream</code> is annoying in this case, and this prompted me to write my own little <code>Formatter</code> class. I am curious if the implementation of this class or the use of it introduces any Undefined Behavior.</p> <p>In particular, is this line fully-defined:</p> <pre><code>Reject( Formatter() &lt;&lt; "Error Recieved" &lt;&lt; 42 &lt;&lt; " " &lt;&lt; some_code &lt;&lt; " '" &lt;&lt; some_msg &lt;&lt; "'"); </code></pre> <p>My belief is that it is OK, but I wanted peer-review.</p> <p>Three main points of concern:</p> <ol> <li>Is there a double-assignment within a single sequence point? Is it UB? </li> <li>Do I have a problem with the lifetime of temporaries?</li> <li>Does my <code>Formatter</code> class (or the intended use of it) introduce any UB?</li> </ol> <p>The <code>Formatter</code> class has both a (templatized) <code>operator&lt;&lt;</code> and an <code>operator std::string</code>. The intent is to use the <code>Formatter()</code> class as a temporary in place of a <code>std::string</code> parameter for any function taking a <code>const std::string&amp;</code>.</p> <p>Here is the class definition:</p> <pre><code>class Formatter { public: Formatter() {}; template&lt;class Field&gt; Formatter&amp; operator&lt;&lt;(Field f) { ss_ &lt;&lt; f; return *this; } operator std::string() const { return ss_.str(); } private: std::stringstream ss_; }; </code></pre> <p>And here is a complete test harness, including the above definition. You should be able to compile &amp; run as-is. Do you see any UB?</p> <pre><code>#include &lt;cstdlib&gt; #include &lt;string&gt; #include &lt;sstream&gt; #include &lt;iostream&gt; class Formatter { public: Formatter() {}; template&lt;class Field&gt; Formatter&amp; operator&lt;&lt;(Field f) { ss_ &lt;&lt; f; return *this; } operator std::string() const { return ss_.str(); } private: std::stringstream ss_; }; void Reject(const std::string&amp; msg) { std::cout &lt;&lt; "Recieved Message: '" &lt;&lt; msg &lt;&lt; "'" &lt;&lt; std::endl; } int main() { const char&amp; some_code = 'A'; const char* some_msg = "Something"; Reject( Formatter() &lt;&lt; "Error Recieved" &lt;&lt; 42 &lt;&lt; " " &lt;&lt; some_code &lt;&lt; " '" &lt;&lt; some_msg &lt;&lt; "'"); } </code></pre>

226

<p>I'm creating some sort of "portfolio" website for my self (a ton of placeholder content right now...) and I was wondering if I could improve the semantics of the HTML<del>5</del> any further, especially the <code>article</code> stuff.</p> <p>I'm not completely sure if I should use <code>section</code> elements inside it. I read through a number of HTML5 "guides" and a few of the element specs, but they often have different positions on this.</p> <p>I think using sections would add to the semantics since the slides are a different "part/section" of the "article".</p> <p>Don't rant about the CSS; it's generated by LESS.</p> <p>The site can be viewed <a href="http://bonsaiden.no.de/" rel="nofollow">here</a>.</p> <p><strong>Manually formatted HTML</strong></p> <pre><code>&lt;!DOCTYPE html&gt; &lt;html&gt; &lt;head&gt; &lt;title&gt;A Python Twitter Client | BonsaiDen&lt;/title&gt; &lt;link rel="shortcut icon" href="/images/favicon.ico"&gt; &lt;link rel="stylesheet" href="http://fonts.googleapis.com/css?family=Ubuntu:regular,bold"&gt; &lt;link rel="stylesheet" href="/stylesheets/style.css"&gt; // will get copied to a local file sooner or later &lt;!--[if lt IE 9]&gt; &lt;script src="http://html5shim.googlecode.com/svn/trunk/html5.js"&gt;&lt;/script&gt; &lt;![endif]--&gt; &lt;/head&gt; &lt;body&gt; // the content &lt;article&gt; // quite some divs here &lt;div&gt; &lt;div id="content"&gt; // maybe use section? // gets replaced via ajax &lt;header data-page="/atarashii"&gt; &lt;h1 class="small"&gt;A Python Twitter Client&lt;/h1&gt; &lt;div class="external"&gt; &lt;a href="https://github.com/BonsaiDen/Atarashii"&gt;Go to Project &amp;#x27A4;&lt;/a&gt; &lt;/div&gt; &lt;div class="clear"&gt;&lt;/div&gt; // always hate these clear things... &lt;/header&gt; &lt;div&gt; &lt;p&gt;A Twitter Client for GNOME...&lt;/p&gt; &lt;/div&gt; // ajax end &lt;/div&gt; &lt;div id="slideshow"&gt; // maybe use section? &lt;header&gt; &lt;h1 id="slideTitle"&gt;[SlideShowItem Title]&lt;/h1&gt; &lt;/header&gt; &lt;div id="slideContent"&gt; &lt;p&gt;[Slideshow Image]&lt;/p&gt; &lt;/div&gt; &lt;/div&gt; &lt;div class="clear"&gt;&lt;/div&gt; &lt;/div&gt; &lt;/article&gt; &lt;header&gt; // navigation, surprise! &lt;nav&gt; // really happy with this &lt;ul&gt; &lt;li class="left"&gt; &lt;h1&gt;Projects&lt;/h1&gt; &lt;ul&gt; &lt;li&gt;&lt;a href="/garden"&gt;JavaScript Garden&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="/shooter"&gt;NodeGame: Shooter&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="/atarashii" class="active"&gt;Atarashii&lt;/a&gt;&lt;/li&gt; &lt;/ul&gt; &lt;/li&gt; &lt;li&gt; &lt;h1&gt;Code&lt;/h1&gt; &lt;ul&gt; &lt;li&gt;&lt;a href="/neko"&gt;neko.js&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="/bison"&gt;BiSON.js&lt;/a&gt;&lt;/li&gt; &lt;/ul&gt; &lt;/li&gt; &lt;li&gt; &lt;h1&gt;Web&lt;/h1&gt; &lt;ul&gt; &lt;li&gt;&lt;a href="/stackoverflow"&gt;Stack Overflow&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="/github"&gt;GitHub&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="/website"&gt;The Website&lt;/a&gt;&lt;/li&gt; &lt;/ul&gt; &lt;/li&gt; &lt;li class="right"&gt; &lt;h1&gt;ME&lt;/h1&gt; &lt;ul class="info"&gt; &lt;li&gt;&lt;a href="/me"&gt;Ivo Wetzel&lt;/a&gt;&lt;/li&gt; &lt;li class="simple"&gt; // div div div :/ &lt;div&gt; &lt;div id="picture"&gt; &lt;img src="images/snufkin.png" alt="Ivo Wetzel"/&gt; &lt;a href="/me"&gt;&lt;/a&gt; &lt;/div&gt; &lt;ul&gt; &lt;li class="first"&gt;&lt;a href="http://twitter.com/BonsaiDen"&gt;Twitter&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="mailto: [email protected]"&gt;E-Mail&lt;/a&gt;&lt;/li&gt; &lt;/ul&gt; &lt;div class="clear"&gt;&lt;/div&gt; &lt;/div&gt; &lt;/li&gt; &lt;/ul&gt; &lt;/li&gt; &lt;/ul&gt; &lt;/nav&gt; &lt;/header&gt; // no real content so far but a background image thingy &lt;footer&gt;&lt;/footer&gt; &lt;script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js"&gt;&lt;/script&gt; &lt;script src="/javascripts/page.js"&gt;&lt;/script&gt; &lt;/body&gt; &lt;/html&gt; </code></pre>

239

<p>How can I clean this up?</p> <pre><code>std::wstring LinkResolve::ResolveLink( const std::wstring&amp; source ) const { HRESULT errorCheck; wchar_t linkTarget[MAX_PATH]; wchar_t expandedTarget[MAX_PATH]; wchar_t arguments[INFOTIPSIZE]; ATL::CComPtr&lt;IPersistFile&gt; ipf; errorCheck = ipf.CoCreateInstance(CLSID_ShellLink, 0, CLSCTX_INPROC_SERVER); if (!SUCCEEDED(errorCheck)) { throw _com_error(errorCheck); } errorCheck = ipf-&gt;Load(source.c_str(), 0); ATL::CComPtr&lt;IShellLink&gt; shellLink; errorCheck = ipf-&gt;QueryInterface(&amp;shellLink); if (!SUCCEEDED(errorCheck)) { throw _com_error(errorCheck); } errorCheck = shellLink-&gt;Resolve(0, SLR_NO_UI); if (!SUCCEEDED(errorCheck)) { throw _com_error(errorCheck); } errorCheck = shellLink-&gt;GetPath(linkTarget, MAX_PATH, 0, SLGP_RAWPATH); if (!SUCCEEDED(errorCheck)) { throw _com_error(errorCheck); } ExpandEnvironmentStringsW(linkTarget, expandedTarget, MAX_PATH); errorCheck = shellLink-&gt;GetArguments(arguments, INFOTIPSIZE); if (SUCCEEDED(errorCheck)) { return std::wstring(expandedTarget) + L" " + arguments; } else { return expandedTarget; } } </code></pre>

259

<p>I'm trying to design a well defined yet simple interface for the unit of work and repository patterns. My UoW's are exposed to services and services then "get repositories" that it needs to query. I know returning <code>IQueryable&lt;T&gt;</code> for repositories is a religious war. Because repositories are only exposed to the service, all queries are performed inside the service and therefore I can test the queries. Is there anything I should change for these interfaces? All criticisms are greatly appreciated!</p> <pre><code>public interface IUnitOfWork : IDisposable { bool IsActive { get; } bool WasCommitted { get; } /// &lt;summary&gt; /// Commits all changes made on the unit of work. /// &lt;/summary&gt; void Commit(); bool WasRolledBack { get; } /// &lt;summary&gt; /// Rolls back all changes made on the unit of work. /// &lt;/summary&gt; void Rollback(); /// &lt;summary&gt; /// Returns an instance of an entity with the specified key that is attached to the unit of work without /// loading the entity from a repository. /// &lt;/summary&gt; /// &lt;param name="id"&gt;&lt;/param&gt; /// &lt;returns&gt;&lt;/returns&gt; T Load&lt;T&gt;(int id) where T : class; void Attach&lt;T&gt;(T entity) where T : class, IIdentifiable; void Detach&lt;T&gt;(T entity) where T : class; IRepository&lt;T&gt; GetRepository&lt;T&gt;() where T : class; } public interface IRepository&lt;T&gt; where T : class { IUnitOfWork UnitOfWork { get; } void Add(T entity); void Remove(T entity); /// &lt;summary&gt; /// Returns an instance of an entity with the specified key that is attached to the unit of work by loading /// the entity from the repository. /// &lt;/summary&gt; /// &lt;param name="id"&gt;&lt;/param&gt; /// &lt;returns&gt;&lt;/returns&gt; T Get(int id); IQueryable&lt;T&gt; All(); } </code></pre>

276

<p>I've got a flat array of &lt; 1000 items and I need to find the indices of a smaller tuple/array within the array. The tuple to find can be a varying length (generally between 2 and 5 items, order is important). </p> <p>This is my initial naive implementation. My main concerns are:</p> <ol> <li>This seems like a CS 101 problem, so I'm pretty sure I'm overdoing it. </li> <li>Readability. I can break this down into smaller methods, but it's essentially a utility function in a much larger class. I guess I could extract it into its own class, but that feels like overkill as well. As-is, it's just too long for me to grok the whole thing in one pass.</li> </ol> <p></p> <pre><code>public int[] findIndices(final Object[] toSearch, final Object[] toFind) { Object first = toFind[0]; List&lt;Integer&gt; possibleStartIndices = new ArrayList&lt;Integer&gt;(); int keyListSize = toFind.length; for (int i = 0; i &lt;= toSearch.length - keyListSize; i++) { if (first.equals(toSearch[i])) { possibleStartIndices.add(i); } } int[] indices = new int[0]; for (int startIndex : possibleStartIndices) { int endIndex = startIndex + keyListSize; Object[] possibleMatch = Arrays.copyOfRange(toSearch, startIndex, endIndex); if (Arrays.equals(toFind, possibleMatch)) { indices = toIndexArray(startIndex, endIndex); break; } } return indices; } private int[] toIndexArray(final int startIndex, final int endIndex) { int[] indices = new int[endIndex - startIndex]; for (int i = 0; i &lt; indices.length; i++) indices[i] = startIndex + i; return indices; } </code></pre>

278

<p>Similar piece of code to that I recently posted as:</p> <p><a href="https://codereview.stackexchange.com/questions/259/the-same-if-block-over-and-over-again-oh-my">Resolving a link</a></p> <p>I have another piece of code which cannot be as easily extracted out into a method:</p> <pre><code>#define THROW_LAST_WINDOWS_ERROR()\ WindowsApi::Exception::Throw(::GetLastError(), __FILE__, __LINE__) #define THROW_MANUAL_WINDOWS_ERROR(x)\ WindowsApi::Exception::Throw(x, __FILE__, __LINE__) Process CreateNormalProcess( ProcessSnapshot *parent, const UNICODE_STRING&amp; name, const unsigned __int32 pid, const std::vector&lt;ToolHelpThread&gt;&amp; threads ) { std::wstring nameStr(name.Buffer, name.Length/sizeof(wchar_t)); std::wstring commandLine; std::wstring mainModulePath; std::wstring error; std::vector&lt;Module&gt; modules; try { using WindowsApi::Dll::NtDll; using WindowsApi::AutoArray; HANDLE hProc = OpenProcess( PROCESS_VM_READ | PROCESS_QUERY_INFORMATION, FALSE, pid); if (hProc == 0) { THROW_LAST_WINDOWS_ERROR(); } //Populate the process environment block NtDll ntDll; PEB peb; AutoArray procInfoBuf = ntDll.NtQueryInformationProcess( ProcessBasicInformation, hProc, sizeof(PROCESS_BASIC_INFORMATION) ); BOOL rpmError = ReadProcessMemory( hProc, procInfoBuf.GetAs&lt;PROCESS_BASIC_INFORMATION&gt;()-&gt;PebBaseAddress, &amp;peb, sizeof(peb), 0); if (rpmError == 0) { THROW_LAST_WINDOWS_ERROR(); } RTL_USER_PROCESS_PARAMETERS procParameters; rpmError = ReadProcessMemory(hProc, peb.ProcessParameters, &amp;procParameters, sizeof(procParameters), 0); if (rpmError == 0) { THROW_LAST_WINDOWS_ERROR(); } commandLine.assign(ReadRemoteUnicodeString(hProc, procParameters.CommandLine)); mainModulePath.assign(ReadRemoteUnicodeString(hProc, procParameters.ImagePathName)); PEB_LDR_DATA ldrData; rpmError = ReadProcessMemory(hProc, peb.Ldr, static_cast&lt;void *&gt;(&amp;ldrData), sizeof(PEB_LDR_DATA), 0); if (rpmError == 0) { THROW_LAST_WINDOWS_ERROR(); } void * endPointer = static_cast&lt;void *&gt; (reinterpret_cast&lt;char *&gt;(peb.Ldr) + (reinterpret_cast&lt;char *&gt;(&amp;ldrData.InLoadOrderModuleList) - reinterpret_cast&lt;char *&gt;(&amp;ldrData))); void * currentListEntry = ldrData.InLoadOrderModuleList.Flink; while (currentListEntry != endPointer) { LDR_MODULE loaderModule; rpmError = ReadProcessMemory( hProc, currentListEntry, &amp;loaderModule, sizeof(loaderModule), 0); if (rpmError == 0) { THROW_LAST_WINDOWS_ERROR(); } std::wstring moduleName = ReadRemoteUnicodeString(hProc, loaderModule.FullDllName); modules.push_back(Module( moduleName, loaderModule.BaseAddress, loaderModule.SizeOfImage )); currentListEntry = loaderModule.InLoadOrderModuleList.Flink; } CloseHandle(hProc); } catch (const ErrorAccessDeniedException&amp;) { error.assign(L"ERROR: Could not access additional information because access " L"was denied while attempting to open the process. Are you admin? Do you " L"have SeDebugPrivilege?"); } catch (const ErrorInvalidParameterException&amp;) { error.assign(L"ERROR: The process terminated before additional information " L"could be extracted"); } catch (const ErrorPartialCopyException&amp;) { error.assign(L"ERROR: Couldn't copy a data structure from this process. Either " L"the process terminated before information extraction, or you are running " L"the 32 bit version of pevFind on a 64 bit machine."); } if (!error.empty()) { if (nameStr.empty()) { nameStr = error; } if (commandLine.empty()) { commandLine = error; } if (mainModulePath.empty()) { mainModulePath = error; } } return Process( parent, pid, nameStr, commandLine, mainModulePath, threads, modules); } </code></pre> <p>The problem here is twofold:</p> <ol> <li>I can't extract out the duplicated if blocks into a method, because it's necessary that they embed the <code>__FILE__</code> and <code>__LINE__</code>.</li> <li><p>I can't put the conditional check into a macro, because the controlled method spans multiple lines:</p> <pre><code>MYMACRO( Function( Call, Spanning, Multiple, Lines)); </code></pre> <p>doesn't seem to expand correctly.</p></li> </ol>

281

<pre><code>void removeForbiddenChar(string* s) { string::iterator it; for (it = s-&gt;begin() ; it &lt; s-&gt;end() ; ++it){ switch(*it){ case '/':case '\\':case ':':case '?':case '"':case '&lt;':case '&gt;':case '|': *it = ' '; } } } </code></pre> <p>I used this function to remove a string that has any of the following character: \, /, :, ?, ", &lt;, >, |. This is for a file's name. This program runs fine. It simply change a character of the string to a blank when the respective character is the forbidden character. However, I have a feeling against this use of switch statement. I simply exploit the case syntax here, but this, somehow nags me. I just don't like it. Anybody else got a better suggestion of a better implementation in this case?</p>

283

<p>This is some of the code I have:</p> <pre><code>[window setLevel:kCGScreenSaverWindowLevel]; [window setOpaque:NO]; [window setStyleMask:0]; [window setBackgroundColor:[NSColor colorWithCalibratedWhite:0.0 alpha:0.3]]; [window setAlphaValue:0]; [window setFrame:[window frameRectForContentRect:[[window screen] frame]] display:YES animate:YES]; [window makeKeyAndOrderFront:self]; [[window animator] setAlphaValue:1.0]; </code></pre> <p>I was just wondering if there was any way to compact it, all of those commands to my window. Any ways to improve it too?</p>

286

<p>I have created this code for user error logging, and I am wondering if there is anything that can be improved. The point is that this error handler would ONLY catch user errors created in-code by trigger_error(), and would display, log, and/or email the error, depending on the config settings. The error logging class is loaded by an autoloader function. For production, all error levels would be set to 0, and the user error handler would never be set, and the class would never be loaded.</p> <p><strong>Config file:</strong></p> <pre><code> // user error display level (change for production) define('LEV_USER_ERROR_DISPLAY_LEVEL', E_USER_ERROR); // user error logging level (change for production) define('LEV_USER_ERROR_LOG_LEVEL', E_USER_ERROR | E_USER_WARNING | E_USER_NOTICE); // user error email alert level define('LEV_USER_ERROR_EMAIL_LEVEL', 0); // user error email address list (e.g. '[email protected], [email protected]') define('LEV_USER_ERROR_EMAIL_ADDRESSES', ''); </code></pre> <p><strong>Init file:</strong></p> <pre><code> // set user error handler if (LEV_USER_ERROR_LOG_LEVEL | LEV_USER_ERROR_DISPLAY_LEVEL | LEV_USER_ERROR_EMAIL_LEVEL) { set_error_handler('lev_user_error_handler::user_error_handler', LEV_USER_ERROR_LOG_LEVEL | LEV_USER_ERROR_DISPLAY_LEVEL | LEV_USER_ERROR_EMAIL_LEVEL); } </code></pre> <p><strong>Error logging class file:</strong></p> <pre><code>&lt;?php // user error handler class lev_user_error_handler { // user error handler public static function user_error_handler($error_level, $message, $file_name, $line_number) { if ((LEV_USER_ERROR_LOG_LEVEL | LEV_USER_ERROR_DISPLAY_LEVEL) == 0) return true; switch ($error_level) { case E_USER_ERROR: if (LEV_USER_ERROR_DISPLAY_LEVEL &amp; E_USER_ERROR) { echo '[' . date('Y-m-d h:i:s') . '] User Level Error: "' . $message . '", File: "'.$file_name.'", Line: '.$line_number.'&lt;br /&gt;'; } if (LEV_USER_ERROR_LOG_LEVEL &amp; E_USER_ERROR) { error_log('[' . date('Y-m-d h:i:s') . '] User Error: "' . $message . '", File: "'.$file_name.'", Line: '.$line_number.', Request: "' . $_SERVER['ORIG_PATH_INFO'] . "\"\n", 3, 'application/logs/user_error_log.txt'); } if (LEV_USER_ERROR_EMAIL_LEVEL &amp; E_USER_ERROR) { error_log('[' . date('Y-m-d h:i:s') . '] User Error: "' . $message . '", File: "'.$file_name.'", Line: '.$line_number.', Request: "' . $_SERVER['ORIG_PATH_INFO'] . '"', 1, LEV_USER_ERROR_EMAIL_ADDRESSES, 'From: no-reply@' . preg_replace('/^.+?\./i', '', $_SERVER['SERVER_NAME'])); } die; break; case E_USER_WARNING: if (LEV_USER_ERROR_DISPLAY_LEVEL &amp; E_USER_WARNING) { echo '[' . date('Y-m-d h:i:s') . '] User Level Warning: "' . $message . '", File: "'.$file_name.'", Line: '.$line_number.'&lt;br /&gt;'; } if (LEV_USER_ERROR_LOG_LEVEL &amp; E_USER_WARNING) { error_log('[' . date('Y-m-d h:i:s') . '] User Warning: "' . $message . '", File: "'.$file_name.'", Line: '.$line_number.', Request: "' . $_SERVER['ORIG_PATH_INFO'] . "\"\n", 3, 'application/logs/user_error_log.txt'); } if (LEV_USER_ERROR_EMAIL_LEVEL &amp; E_USER_WARNING) { error_log('[' . date('Y-m-d h:i:s') . '] User Error: "' . $message . '", File: "'.$file_name.'", Line: '.$line_number.', Request: "' . $_SERVER['ORIG_PATH_INFO'] . '"', 1, LEV_USER_ERROR_EMAIL_ADDRESSES, 'From: no-reply@' . preg_replace('/^.+?\./i', '', $_SERVER['SERVER_NAME'])); } break; case E_USER_NOTICE: if (LEV_USER_ERROR_DISPLAY_LEVEL &amp; E_USER_NOTICE) { echo '[' . date('Y-m-d h:i:s') . '] User Level Notice: "' . $message . '", File: "'.$file_name.'", Line: '.$line_number.'&lt;br /&gt;'; } if (LEV_USER_ERROR_LOG_LEVEL &amp; E_USER_NOTICE) { error_log('[' . date('Y-m-d h:i:s') . '] User Notice: "' . $message . '", File: "'.$file_name.'", Line: '.$line_number.', Request: "' . $_SERVER['ORIG_PATH_INFO'] . "\"\n", 3, 'application/logs/user_error_log.txt'); } if (LEV_USER_ERROR_EMAIL_LEVEL &amp; E_USER_NOTICE) { error_log('[' . date('Y-m-d h:i:s') . '] User Error: "' . $message . '", File: "'.$file_name.'", Line: '.$line_number.', Request: "' . $_SERVER['ORIG_PATH_INFO'] . '"', 1, LEV_USER_ERROR_EMAIL_ADDRESSES, 'From: no-reply@' . preg_replace('/^.+?\./i', '', $_SERVER['SERVER_NAME'])); } break; default: // call PHP internal error handler return false; } // do not call PHP internal error handler return true; } } ?&gt; </code></pre>

294

<p>I've just started learning CSS/HTML a week ago and I made a quick site today. It looks pretty good, but I think that I reused/wrote some really messy CSS. This is because I haven't used the <code>float</code> property in CSS too well, so I keep using <code>position:relative</code> and <code>top</code> to offset the <code>float</code>.</p> <p><div class="snippet" data-lang="js" data-hide="false" data-console="false" data-babel="false"> <div class="snippet-code"> <pre class="snippet-code-css lang-css prettyprint-override"><code>/* General Elements* / body { background: #53777a; font-family: Garamond, Baskerville, "Baskerville Old Face", "Hoefler Text", "Times New Roman", serif; } h1 { font-size: 28pt; } h2 {} p {} a:link { color: black; text-decoration: none; } a:visited { color: purple; text-decoration: none; } a:hover { color: green; text-decoration: underline; } a:active { color:yellow; text-decoration: none; } /* Curvy Shapes */ #wrapper, #footer { -moz-border-radius-bottomright: 50px; -moz-border-radius-topleft: 50px; -moz-border-radius-topright: 50px; -moz-border-radius-bottomleft: 50px; border-bottom-right-radius: 50px; border-top-left-radius: 50px; border-top-right-radius: 50px; border-bottom-left-radius: 50px; } #links { -moz-border-radius-bottomright: 50px; -moz-border-radius-bottomleft: 50px; border-bottom-right-radius: 50px; border-bottom-left-radius: 50px; } #header { -moz-border-radius-topleft: 50px; -moz-border-radius-topright: 50px; border-top-left-radius: 50px; border-top-right-radius: 50px; } /* Structure */ #wrapper { width: 900px; margin: 0 auto; margin-top: 30px; overflow: auto; background: #E0E4CC; padding: 20px; -moz-border-radius-bottomright: 50px; -moz-border-radius-topleft: 50px; -moz-border-radius-topright: 50px; -moz-border-radius-bottomleft: 50px; border-bottom-right-radius: 50px; border-top-left-radius: 50px; border-top-right-radius: 50px; border-bottom-left-radius: 50px; } #header { text-align: center; background: #ECD078; padding: 4px; } #links { width: 900px; background-color: #A7DBD8; position: relative; top: -20px; text-align: center; } #links ul { list-style-type: none; padding: 5px; } #links li{ display: inline; font-size: 14pt; padding: 20px; } .sidebar_left { float: left; width: 180px; margin-left: 10px; position: relative; top: -10px; text-align: justify; line-height: 150%; } #post { float: right; width: 680px; margin-left: 0px; margin-right: 10px; position: relative; top: -25px; text-align: justify; line-height: 150%; } #post b { font-size: 18pt; text-decoration: underline; } #content { float: right; width: 680px; margin-left: 0px; margin-right: 10px; position: relative; top: -25px; text-align: justify; text-indent: 25px; line-height: 150%; } #social { float: right; } #footer { width: 890px; background: #A7DBD8; float: left; padding: 5px; text-align: right; } #footer b { margin-left: 10px; } /* End Structure */ /*images*/ .navimg { width: 2px; height: 20px; } #tree { width: 175px; height: 200px; float: right; margin-left: 20px; margin-top: 24px; } #blackwhite { width: 200px; height: 125px; float: left; margin-right: 20px; margin-top: 10px; } #quickshot { width: 125px; height: 100px; display: block; margin-left: auto; margin-right: auto; }</code></pre> <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;?xml version="1.0" encoding="utf-8"?&gt; &lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd"&gt; &lt;html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en"&gt; &lt;head&gt; &lt;title&gt;Kevin Li&lt;/title&gt; &lt;link rel="stylesheet" type="text/css" href="css/style.css" /&gt; &lt;/head&gt; &lt;body&gt; &lt;div id="wrapper"&gt; &lt;div id="header"&gt; &lt;h1&gt;Kevin Li&lt;/h1&gt; &lt;/div&gt; &lt;div id="links"&gt; &lt;ul&gt; &lt;li&gt;&lt;a href="#"&gt;Home&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="#"&gt;Biography&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="#"&gt;Portfolio&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="#"&gt;Blog&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="#"&gt;Images&lt;/a&gt;&lt;/li&gt; &lt;li&gt;&lt;a href="#"&gt;Contact Me&lt;/a&gt;&lt;/li&gt; &lt;/ul&gt; &lt;/div&gt; &lt;div class="sidebar_left"&gt; Lorem ipsum dolor sit amet...&lt;br /&gt; &lt;/div&gt; &lt;div id="post"&gt; &lt;b&gt;Introduction&lt;/b&gt;&lt;br /&gt; &lt;i&gt;Thursday, January 27, 2011&lt;/i&gt; &lt;/div&gt; &lt;br /&gt; &lt;div id="content"&gt; &lt;img id="tree" src="images/c2_i6.png" /&gt; &lt;p&gt; Lorem ipsum dolor sit amet...&lt;br /&gt; &lt;br /&gt; &lt;img id="blackwhite" src="images/c3_i7.png" /&gt; Ut venenatis diam nunc...&lt;br /&gt; &lt;br /&gt; &lt;/p&gt; &lt;/div&gt; &lt;div id="footer"&gt; &lt;b&gt;Copyright 2010 Kevin Li&lt;/b&gt; &lt;/div&gt; &lt;/div&gt; &lt;/body&gt; &lt;/html&gt;</code></pre> </div> </div> </p> <p>By the way, I know it doesn't validate. I am working on that now.</p>

296

<p>I am in the process of learning Clojure. I am fairly new to functional programming and would like to know if my code smells or if there are any performance implications with my approach.</p> <pre><code>; Returns the the given sequence with the given item appended to it. (defn snoc [xs x] (concat xs [x])) ; Returns the Fibonacci sequence up to the highest number less than max. (defn fib [max] (loop [a 1, b 1, acc [1]] (if (&gt; b max) acc (recur b (+ a b) (snoc acc b))))) ; Project Euler Problem 2: Attempt A (defn pe2a [] (reduce + (filter even? (fib 4000000)))) </code></pre> <p>For <a href="http://projecteuler.net/index.php?section=problems&amp;id=2">reference</a>:</p> <blockquote> <p>Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 terms will be:</p> <p>1, 2, 3, 5, 8, 13, 21, 34, 55, 89, ...</p> <p>By considering the terms in the Fibonacci sequence whose values do not exceed four million, find the sum of the even-valued terms.</p> </blockquote>

300

<p>I wrote a BST in C a while back and may use it at some point. </p> <pre><code> search_tree tree_make_empty( search_tree tree ) { if ( tree != NULL ) { tree_make_empty( tree-&gt;left ); tree_make_empty( tree-&gt;right ); free( tree ); } return NULL; } tree_position tree_find( CHAR_DATA *target, search_tree tree ) { if ( tree == NULL ) return NULL; if ( target &lt; tree-&gt;hatedata-&gt;target_char ) return tree_find( target, tree-&gt;left ); else if ( target &gt; tree-&gt;hatedata-&gt;target_char ) return tree_find( target, tree-&gt;right ); else return tree; } search_tree tree_insert( HATE_DATA *hatedata, search_tree tree ) { if ( tree == NULL ) { tree = (HATE_NODE * ) malloc( sizeof( HATE_NODE ) ); if ( tree == NULL ) bug( "tree_insert: out of space!" ); else { tree-&gt;hatedata = hatedata; tree-&gt;left = tree-&gt;right = NULL; } } else if ( hatedata-&gt;target_char &lt; tree-&gt;hatedata-&gt;target_char ) tree-&gt;left = tree_insert( hatedata, tree-&gt;left ); else if ( hatedata-&gt;target_char &gt; tree-&gt;hatedata-&gt;target_char ) tree-&gt;right = tree_insert( hatedata, tree-&gt;right ); return tree; } tree_position tree_find_min( search_tree tree ) { if ( tree == NULL ) return NULL; else if ( tree-&gt;left == NULL ) return tree; else return tree_find_min( tree-&gt;left ); } search_tree tree_delete( HATE_DATA *hatedata, search_tree tree ) { tree_position pos; if ( tree == NULL ) bug( "tree_delete: not found" ); else if ( hatedata-&gt;target_char &lt; tree-&gt;hatedata-&gt;target_char ) tree-&gt;left = tree_delete( hatedata, tree-&gt;left ); else if ( hatedata-&gt;target_char &gt; tree-&gt;hatedata-&gt;target_char ) tree-&gt;right = tree_delete( hatedata, tree-&gt;right ); else if ( tree-&gt;left &amp;&amp; tree-&gt;right ) { pos = tree_find_min( tree-&gt;right ); tree-&gt;hatedata = pos-&gt;hatedata; tree-&gt;right = tree_delete( tree-&gt;hatedata, tree-&gt;right ); } else { pos = tree; if ( tree-&gt;left == NULL ) tree = tree-&gt;right; else if ( tree-&gt;right == NULL ) tree = tree-&gt;left; free( pos ); } return tree; } HATE_DATA *tree_retrieve( tree_position pos ) { return pos-&gt;hatedata; } </code></pre> <p>...</p> <pre><code> struct hate_data { CHAR_DATA *target_char; int hate_amount; }; struct hate_node { HATE_DATA *hatedata; search_tree left; search_tree right; }; </code></pre> <p>...</p> <pre><code>mob-&gt;hatedata = tree_make_empty( NULL ); </code></pre> <p>Example use:</p> <pre><code>if ( IS_NPC(victim) ) { HATE_DATA *hatedata; tree_position P; if( ( P = tree_find( ch, victim-&gt;hatedata )) == NULL || tree_retrieve( P )-&gt;target_char != ch ) { int test; hatedata = (HATE_DATA * ) malloc( sizeof( HATE_DATA ) ); hatedata-&gt;target_char = ch; test = number_range( 1, 50 ); hatedata-&gt;hate_amount = test; victim-&gt;hatedata = tree_insert( hatedata, victim-&gt;hatedata ); ch_printf( ch, "It should now hate you for %d.\n\r", test ); } else { hatedata = tree_retrieve(tree_find( ch, victim-&gt;hatedata )); ch_printf(ch, "You are already hated for %d!\n\r", hatedata-&gt;hate_amount ); } } </code></pre> <p>Do you have any suggestions? Does it look okay? Are there any ways to optimize it?</p>

311

<p>Oftentimes I find myself wanting the total number of rows returned by a query even though I only may display 50 or so per page. Instead of doing this in multiple queries like so:</p> <pre><code>SELECT first_name, last_name, (SELECT count(1) FROM sandbox.PEOPLE WHERE trunc(birthday) = trunc(sysdate) ) as totalRows FROM sandbox.PEOPLE WHERE trunc(birthday) = trunc(sysdate); </code></pre> <p>It has been recommended to me to do this:</p> <pre><code>SELECT first_name, last_name, count(*) over () totalRows FROM sandbox.PEOPLE WHERE trunc(birthday) = trunc(sysdate); </code></pre> <p>I am just looking for what is better as far as performance and if performance is a wash. Does this really improve readability of SQL? It is certainly cleaner/easier to write.</p>

326

<p>This JS function is intended to retrieve or place a value into an object with the nested keys as a string.</p> <p>For example</p> <pre><code>var obj = {a: {b: [4]}}; parse_obj_key(obj, "a.b.0") should equal 4. parse_obj_key(obj, "a.c", 2) should add another element to "a" named "c" with value 2. </code></pre> <p>The method works, but I'd like to clean it up if possible (or a more polished implementation which is publicly available). I'd also love to know of any edge-case failures which can be found.</p> <pre><code>function parse_obj_key(obj, loc, val){ var _o = obj; while (true){ var pos = loc.indexOf('.'); if (!_o || typeof _o != 'object'){ $.log("Invalid obj path: " + loc + "\n" + JSON.stringify(obj)); return null; } if (pos === -1){ if (val){ _o[loc] = val; return obj; } else { if (!isNaN(parseInt(loc))) loc = parseInt(loc); return _o[loc]; } } var part = loc.substring(0, pos); var loc = loc.substring(pos + 1); if (!isNaN(parseInt(part))) part = parseInt(part); if (!(part in _o)){ if (val) _o[part] = new object; else return null; } _o = _o[part]; } } </code></pre>

340

<p>This works but there must be a better way:</p> <pre><code>txtBox.InputScope = new InputScope { Names = { new InputScopeName { NameValue = InputScopeNameValue.Text } } }; </code></pre>

341

<p>I started out with the best of intentions, but this form got hacky real fast.</p> <p>It's purpose is to serve as a create new Student form. Also, if you want to view an existing Students information.</p> <p>Think of it as the CRU of CRUD.</p> <p>Here it is:</p> <pre><code>using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Linq; using System.Text; using System.Windows.Forms; using Tutomentor.Branding; using Tutomentor.Data.Repositories; namespace Tutomentor.UI.Students { public partial class StudentInformation : Form { StudentRepository repo = new StudentRepository(); bool IsCreating = false; Student student; public StudentInformation() { InitializeComponent(); LoadComboBoxes(); LoadBranding(); IsCreating = true; } public StudentInformation(int studentID) { InitializeComponent(); LoadComboBoxes(); LoadBranding(); student = repo.FindStudent(studentID); LoadStudentInformation(student); } private void LoadComboBoxes() { cmbGrade.DisplayMember = "Name"; cmbGrade.ValueMember = "ID"; cmbGradeParalelo.DisplayMember = "Name"; cmbGradeParalelo.ValueMember = "ID"; GradeRepository repo = new GradeRepository(); cmbGrade.DataSource = repo.FindAllGrades(); } private void LoadStudentInformation(Student student) { cmbGrade.SelectedValue = student.GradeParalelo.Grade.ID; cmbGradeParalelo.SelectedValue = student.IDGrade; txtRude.Text = student.RUDE.ToString(); txtNombrePadre.Text = student.FatherName; txtProfesionPadre.Text = student.FatherProfession; txtCelularPadre.Text = student.MobilePhoneFather; txtLugarDeTrabajoPadre.Text = student.PlaceofWorkFather; txtNombreMadre.Text = student.MotherName; txtProfesionMadre.Text = student.MotherProfession; txtCelularMadre.Text = student.MobilePhoneMother; txtLugarDeTrabajoMadre.Text = student.PlaceofWorkMother; txtObservaciones.Text = student.Observations; txtNombre.Text = student.Name; txtApellidoPaterno.Text = student.FatherLastName; txtApellidoMaterno.Text = student.MotherLasteName; dtpFechaNacimiento.Value = Convert.ToDateTime(student.DateOfBirth); txtLugarNacimiento.Text = student.PlaceOfBirth; SetSex(student.Sex); txtCarnet.Text = student.Carnet; txtTelefono.Text = student.Telephone; txtCelular.Text = student.MobilePhone; txtDireccion.Text = student.Address; } private void SetSex(string p) { if (p == "M") { sexoMasculino.Checked = true; sexoFemenino.Checked = false; } else { sexoMasculino.Checked = false; sexoFemenino.Checked = true; } } private void LoadBranding() { this.Text = "Tutomentor - Agregando nuevo alumnos."; this.BackColor = Brand.PrimaryColor; panelBorderLeft.BackColor = Brand.HeaderColor; panelBorderRight.BackColor = Brand.HeaderColor; panelSeparator1.BackColor = Brand.SeparatorColor; } private void cmbGrade_SelectedIndexChanged(object sender, EventArgs e) { LoadGradeParalelos(); } private void LoadGradeParalelos() { GradeParaleloRepository repo = new GradeParaleloRepository(); Int64 gradeID = Convert.ToInt64(cmbGrade.SelectedValue); cmbGradeParalelo.DataSource = repo.FindAllGradeParalelos().Where(g =&gt; g.IDGrade == gradeID); } private void btnSave_Click(object sender, EventArgs e) { SaveInformation(); } private void SaveInformation() { if (IsCreating) { Student newStudent = new Student(); Int64 gradeId = Convert.ToInt64(cmbGradeParalelo.SelectedValue); newStudent.IDGrade = gradeId; newStudent.RUDE = Convert.ToInt64(txtRude.Text); /*Parents information.*/ newStudent.FatherName = txtNombrePadre.Text; newStudent.FatherProfession = txtProfesionPadre.Text; newStudent.MobilePhoneFather = FormatPhoneNumber(txtCelularPadre.Text); newStudent.PlaceofWorkFather = txtLugarDeTrabajoPadre.Text; newStudent.MotherName = txtNombreMadre.Text; newStudent.MotherProfession = txtProfesionMadre.Text; newStudent.MobilePhoneMother = FormatPhoneNumber(txtCelularMadre.Text); newStudent.PlaceofWorkMother = txtLugarDeTrabajoMadre.Text; /*newStudent information*/ newStudent.Name = txtNombre.Text; newStudent.FatherLastName = txtApellidoPaterno.Text; newStudent.MotherLasteName = txtApellidoMaterno.Text; newStudent.DateOfBirth = dtpFechaNacimiento.Value.ToShortDateString(); newStudent.PlaceOfBirth = txtLugarNacimiento.Text; newStudent.Sex = sexoMasculino.Checked ? sexoMasculino.Text : sexoFemenino.Text; newStudent.Telephone = FormatPhoneNumber(txtTelefono.Text); newStudent.MobilePhone = FormatPhoneNumber(txtCelular.Text); newStudent.Address = txtDireccion.Text; newStudent.Carnet = FormatPhoneNumber(txtCarnet.Text); newStudent.Observations = txtObservaciones.Text; repo.Add(newStudent); repo.Save(); MessageBox.Show("Se guardo el registro exitosamente.", "Exito!", MessageBoxButtons.OK, MessageBoxIcon.Information, MessageBoxDefaultButton.Button1); ClearForm(); } else { Int64 gradeId = Convert.ToInt64(cmbGradeParalelo.SelectedValue); student.IDGrade = gradeId; student.RUDE = Convert.ToInt64(txtRude.Text); /*Parents information.*/ student.FatherName = txtNombrePadre.Text; student.FatherProfession = txtProfesionPadre.Text; student.MobilePhoneFather = FormatPhoneNumber(txtCelularPadre.Text); student.PlaceofWorkFather = txtLugarDeTrabajoPadre.Text; student.MotherName = txtNombreMadre.Text; student.MotherProfession = txtProfesionMadre.Text; student.MobilePhoneMother = FormatPhoneNumber(txtCelularMadre.Text); student.PlaceofWorkMother = txtLugarDeTrabajoMadre.Text; /*student information*/ student.Name = txtNombre.Text; student.FatherLastName = txtApellidoPaterno.Text; student.MotherLasteName = txtApellidoMaterno.Text; student.DateOfBirth = dtpFechaNacimiento.Value.ToShortDateString(); student.PlaceOfBirth = txtLugarNacimiento.Text; student.Sex = sexoMasculino.Checked ? sexoMasculino.Text : sexoFemenino.Text; student.Telephone = FormatPhoneNumber(txtTelefono.Text); student.MobilePhone = FormatPhoneNumber(txtCelular.Text); student.Address = txtDireccion.Text; student.Carnet = FormatPhoneNumber(txtCarnet.Text); student.Observations = txtObservaciones.Text; repo.Save(); MessageBox.Show("Se guardo el registro exitosamente.", "Exito!", MessageBoxButtons.OK, MessageBoxIcon.Information, MessageBoxDefaultButton.Button1); this.Close(); } } private string FormatPhoneNumber(string p) { return p.Insert(3, "-"); } private void btnClear_Click(object sender, EventArgs e) { ClearForm(); } private void ClearForm() { Action&lt;Control.ControlCollection&gt; func = null; func = (controls) =&gt; { foreach (Control control in controls) if (control is TextBox) (control as TextBox).Clear(); else func(control.Controls); }; func(Controls); } } } </code></pre> <p>I don't know how to improve this class because every line of code is needed.</p>

343

<p>It's clever, but makes me vomit a little:</p> <pre><code>file = '0123456789abcdef123' path = os.sep.join([ file[ x:(x+2) ] for x in range(0,5,2) ]) </code></pre>

346

<p>I wrote a bunch of Ruby code for a book project I've just finished. One criticism is that it is fine code but not very "ruby like". I agree my style was simplified for communication reasons, and although it's procedural code, it still feels "ruby-like" to me. </p> <p>For the representative example below, any ideas on making it more "Ruby like"?</p> <pre><code># Genetic Algorithm in the Ruby Programming Language # The Clever Algorithms Project: http://www.CleverAlgorithms.com # (c) Copyright 2010 Jason Brownlee. Some Rights Reserved. # This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 2.5 Australia License. def onemax(bitstring) sum = 0 bitstring.size.times {|i| sum+=1 if bitstring[i].chr=='1'} return sum end def random_bitstring(num_bits) return (0...num_bits).inject(""){|s,i| s&lt;&lt;((rand&lt;0.5) ? "1" : "0")} end def binary_tournament(pop) i, j = rand(pop.size), rand(pop.size) j = rand(pop.size) while j==i return (pop[i][:fitness] &gt; pop[j][:fitness]) ? pop[i] : pop[j] end def point_mutation(bitstring, rate=1.0/bitstring.size) child = "" bitstring.size.times do |i| bit = bitstring[i].chr child &lt;&lt; ((rand()&lt;rate) ? ((bit=='1') ? "0" : "1") : bit) end return child end def crossover(parent1, parent2, rate) return ""+parent1 if rand()&gt;=rate point = 1 + rand(parent1.size-2) return parent1[0...point]+parent2[point...(parent1.size)] end def reproduce(selected, pop_size, p_cross, p_mutation) children = [] selected.each_with_index do |p1, i| p2 = (i.modulo(2)==0) ? selected[i+1] : selected[i-1] p2 = selected[0] if i == selected.size-1 child = {} child[:bitstring] = crossover(p1[:bitstring], p2[:bitstring], p_cross) child[:bitstring] = point_mutation(child[:bitstring], p_mutation) children &lt;&lt; child break if children.size &gt;= pop_size end return children end def search(max_gens, num_bits, pop_size, p_crossover, p_mutation) population = Array.new(pop_size) do |i| {:bitstring=&gt;random_bitstring(num_bits)} end population.each{|c| c[:fitness] = onemax(c[:bitstring])} best = population.sort{|x,y| y[:fitness] &lt;=&gt; x[:fitness]}.first max_gens.times do |gen| selected = Array.new(pop_size){|i| binary_tournament(population)} children = reproduce(selected, pop_size, p_crossover, p_mutation) children.each{|c| c[:fitness] = onemax(c[:bitstring])} children.sort!{|x,y| y[:fitness] &lt;=&gt; x[:fitness]} best = children.first if children.first[:fitness] &gt;= best[:fitness] population = children puts " &gt; gen #{gen}, best: #{best[:fitness]}, #{best[:bitstring]}" break if best[:fitness] == num_bits end return best end if __FILE__ == $0 # problem configuration num_bits = 64 # algorithm configuration max_gens = 100 pop_size = 100 p_crossover = 0.98 p_mutation = 1.0/num_bits # execute the algorithm best = search(max_gens, num_bits, pop_size, p_crossover, p_mutation) puts "done! Solution: f=#{best[:fitness]}, s=#{best[:bitstring]}" end </code></pre>

354

<p>I'm new to Hibernate so I need some advice/direction on doing Transactions.</p> <p>I have a DAO like</p> <pre><code>public class MyDao extends HibernateDaoSupport implements IMyDao { @Override public Foo getFoo(int id) { return (Foo)getHibernateTemplate().load(Foo.class, id); } } </code></pre> <p>With this setup (using HibernateDaoSupport), will Hibernate/Spring handle transactions for me? Some of the examples I see say yes, others show using</p> <pre><code>Transaction tx = getHibernateTemplate().getSessionFactory().getCurrentSession().beginTransaction(); </code></pre> <p>to get a Transaction in every DAO method.</p> <p>Right now I'm assuming my minimal DAO is correct but I want to do a "larger" transaction that includes a couple of Hibernate calls in one method. Would I use the manual Transaction method there? Do I have to use it everywhere? Thanks.</p>

356

<p>I want to write an Android <a href="http://developer.android.com/reference/android/widget/ListAdapter.html" rel="nofollow"><code>ListAdapter</code></a> to serve data from a database that look like this:</p> <pre><code>CREATE TABLE note (_id integer primary key autoincrement, content text not null) CREATE TABLE tag (_id integer primary key autoincrement, name text not null); CREATE TABLE relation (_id integer primary key autoincrement, noteid integer not null, tagid integer not null, idx integer not null); </code></pre> <p>I use this database to store notes and their associated tags as an ordered list. One requirement of the ListAdapter is that it must be able to update the ListView contents if the underlying data changes. I can query all the notes in the database with this query:</p> <pre><code>SELECT note._id AS noteid, note.content, relation.idx AS tagidx, tag.name FROM note LEFT JOIN relation ON (relation.noteid = note._id) LEFT JOIN tag ON (tag._id = relation.tagid) ORDER BY noteid, tagidx; </code></pre> <p>Which will give me results looking like this (null values shown for clarity):</p> <pre><code>0|foo bar baz|0|x 1|hello world|null|null 2|one more nn|0|yy 2|one more nn|1|y </code></pre> <p>As you can see, a note with more than one tag will be located on more than one row in the result. This means that I can't look at the cursor size to determine the number of notes, I need to traverse the entire Cursor to get a count. I don't want to do that.</p> <p>The solution I have come up with so far is to use two cursors: one with the query mentioned above and one with a query containing the number of rows in the notes table (<code>select count(*) from notes</code>). In the constructor I call <code>intializeCursors()</code>:</p> <pre><code>private void initializeCursors() { notesCursor.moveToFirst(); countCursor.moveToFirst(); count = countCursor.getInt(0); } </code></pre> <p>I have implemented <code>getItem()</code> like this:</p> <pre><code>public Note getItem(int position) { // notes is a List of notes that we have already read. if (position &lt; notes.size()) { return notes.get(position); } int cursorPosition = notes.size(); while (cursorPosition &lt;= position) { // Creates a note by reading the correct number of rows. Note note = NotesDb.noteFrom(notesCursor); notes.add(note); ++cursorPosition; } return notes.get(position); } </code></pre> <p>The adapter assumes that the cursors are being managed by some <a href="http://developer.android.com/reference/android/app/Activity.html" rel="nofollow"><code>Activity</code></a> that has called <a href="http://developer.android.com/reference/android/app/Activity.html#startManagingCursor(android.database.Cursor)" rel="nofollow"><code>startManagingCursor()</code></a> on them.</p> <p>So far so good, I guess. The problem is now how to handle the cursor being <a href="http://developer.android.com/reference/android/database/Cursor.html#requery()" rel="nofollow">requeried</a>. Since I have two cursors I need to register listeners for both of them and when I have received <a href="http://developer.android.com/reference/android/database/DataSetObserver.html#onChanged()" rel="nofollow"><code>onChange()</code></a> for both of them I can <code>initializeCursors()</code> and notify any listeners registered to my <a href="http://developer.android.com/reference/android/widget/ListAdapter.html" rel="nofollow"><code>ListAdapter</code></a> of a change in the its data.</p> <p>The requery scenario is the actual reason that I needed two cursors in the first place. I have not figured out a way to count the number of notes in a required cursor other than asking the database using another cursor.</p> <p>This is the best I have so far. I want to check the sanity of this approach with this group. :-) Is this two cursor approach too complicated? Perhaps I have missed some part of the API that solves this nicely for me?</p>

359

<p>Should my class pass parameters internally or reference class level scoped variables?</p> <p>I'm not sure on the best approach or style for procedure calls that have parameters. Should I go with the class level scoped variables?</p> <pre><code>public class YouOweTheGovernment { public float AmountToPay { get; private set; } public float ArbitraryTaxRate { get; private set; } public float Salary { get; private set; } public YouOweTheGovernment(float taxRate, float salary) { this.ArbitraryTaxRate = taxRate; this.Salary = salary; CalculateAmount(); } private void CalculateAmount() { this.AmountToPay = (this.Salary * (this.ArbitraryTaxRate / 100)); } } </code></pre> <p>Or explicitly pass parameters into a procedure?</p> <pre><code>public class YouOweTheGovernment { public float AmountToPay { get; private set; } public float ArbitraryTaxRate { get; private set; } public float Salary { get; private set; } public YouOweTheGovernment(float taxRate, float salary) { this.ArbitraryTaxRate = taxRate; this.Salary = salary; CalculateAmount(this.Salary, this.ArbitraryTaxRate); } private void CalculateAmount(float salary, float taxRate) { this.AmountToPay = (salary * (taxRate / 100)); } } </code></pre> <p>In my contrived example I think the first is clearer, but as a class grows in size and complexity it would make it harder to track what is coming from where.</p>

362

<p>I've built a custom control that generates a tab style navigation. Each page might have different tabs to display, the aim was to modularise it so I can make global changes to all the tabs.</p> <p><strong>TabMenu.ascx</strong></p> <pre><code>&lt;%@ Control Language="C#" AutoEventWireup="true" CodeFile="TabMenu.ascx.cs" Inherits="TabMenu" %&gt; &lt;asp:Panel runat="server" ID="TabMenuWrapper" CssClass="tabWrapper"&gt; &lt;/asp:Panel&gt; </code></pre> <p><strong>TabMenu.ascx.cs</strong></p> <pre><code>using System; using System.Collections.Generic; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; using System.Collections; public partial class TabMenu : System.Web.UI.UserControl { public string TabGroup { get; set; } // The tab group this control belongs to public int SelectedTab { get; set; } // Index of selected tab protected void Page_Load(object sender, EventArgs e) { ArrayList tabCollection = new ArrayList(); MenuTab myTab; // Artorking tab group if (this.TabGroup.ToLower() == "artwork") { myTab = new MenuTab() { linkURL = "artworkHome.aspx", linkText = "First!" }; tabCollection.Add(myTab); myTab = new MenuTab() { linkURL = "artworkHome.aspx", linkText = "Second!" }; tabCollection.Add(myTab); myTab = new MenuTab() { linkURL = "artworkHome.aspx", linkText = "3rd!" }; tabCollection.Add(myTab); myTab = new MenuTab() { linkURL = "artworkHome.aspx", linkText = "Fourth!" }; tabCollection.Add(myTab); } // Add tabs to the page for (int i = 0; i &lt; tabCollection.Count; i++) { MenuTab thisTab = ((MenuTab)(tabCollection[i])); thisTab.CreateTab(); if (i == this.SelectedTab) { thisTab.tabPanel.CssClass = "tab tabSelected"; } TabMenuWrapper.Controls.Add(thisTab.tabPanel); } TabMenuWrapper.Controls.Add(new Panel(){CssClass = "clear"}); } } // A menu tab public class MenuTab { public string linkURL; public string linkText; public HyperLink tabLink; public Panel tabPanel; // Create internal controls public void CreateTab() { this.tabLink = new HyperLink() { NavigateUrl = this.linkURL, Text = this.linkText }; this.tabPanel = new Panel() { CssClass = "tab" }; this.tabPanel.Controls.Add(this.tabLink); } } </code></pre> <p>Used as follows:</p> <pre><code>&lt;CrystalControls:TabMenu runat="server" ID="TopMenu" TabGroup="Artwork" SelectedTab="1" /&gt; </code></pre> <p>And renders like:</p> <pre><code>&lt;div class="tab"&gt; &lt;a href="Controls/artworkHome.aspx"&gt;First!&lt;/a&gt; &lt;/div&gt;&lt;div class="tab tabSelected"&gt; &lt;a href="Controls/artworkHome.aspx"&gt;Second!&lt;/a&gt; &lt;/div&gt;&lt;div class="tab"&gt; &lt;a href="Controls/artworkHome.aspx"&gt;3rd!&lt;/a&gt; &lt;/div&gt;&lt;div class="tab"&gt; &lt;a href="Controls/artworkHome.aspx"&gt;Fourth!&lt;/a&gt; &lt;/div&gt;&lt;div class="clear"&gt; &lt;/div&gt; &lt;/div&gt; </code></pre> <p>Is this a good design?</p>

364

<p>I've had to make several functions to turn some structures into strings. I am a still green when it comes C so I am unsure if I am doing this a very awkward way. The system I am coding for does not have snprintf, I know that would be far more elegant, however I cannot use it. Any advice?</p> <pre><code>int device_to_string(char* const asString, pDevice dev, size_t maxLength) { char* ipAsString; size_t actualLength; struct in_addr addr; if (dev == NULL) { return NULL_ERROR; } addr.s_addr = dev-&gt;ip; ipAsString = inet_ntoa(addr); actualLength = strlen("name=") + strlen(dev-&gt;name) + strlen("&amp;ip=") + strlen(ipAsString) + strlen("&amp;mac=") + strlen(dev-&gt;mac) + strlen("&amp;type=") + strlen(dev-&gt;type) + 1; if (actualLength &gt; maxLength) { return SIZE_ERROR; } strncat(asString, "name=", strlen("name=")); strncat(asString, dev-&gt;name, strlen(dev-&gt;name)); strncat(asString, "&amp;ip=", strlen("&amp;ip=")); strncat(asString, ipAsString, strlen(ipAsString)); strncat(asString, "&amp;mac=", strlen("&amp;mac=")); strncat(asString, dev-&gt;mac, strlen(dev-&gt;mac)); strncat(asString, "&amp;type=", strlen("&amp;type=")); strncat(asString, dev-&gt;type, strlen(dev-&gt;type)); asString[actualLength] = '\0'; return NO_ERROR; } </code></pre>

365

<p>I've been doing a simple Tic-Tac-Toe with PHP, generating only HTML code.</p> <p>A few notes:</p> <ul> <li>I didn't bother yet to give an AI to the opponents (the Os), and it is intentional. </li> <li>There is no CSS style to it, I intend to append it with a css file. </li> <li>tictactoe.php is naturally the name of the script itself, so each links are refering to the page itself.</li> </ul> <p>Now I don't know if I did everything correctly, here are my concern:</p> <ul> <li>If I want to expand the functionalities of the game in the future (adding javascript, opponent AIs, new game features), I fear that the structure of the code is not adapted for it. Should I change my code so it is Object Oriented? <strong>EDIT</strong> I have in mind to add new feature to the game, like powers who would change the state of the board, like rewind to a previous state and; some css and javascript in a non-intrusive way and add some way to check if options are disabled (like javascript/flash), or check for the version of the browser for html5/css3 features.</li> <li>As for now, it is easy to "cheat" and directly introduce the wished board state. I would like to prevent that, and if possible without using javascript, as I want the game to be playable also without it.</li> </ul> <pre><code>&lt;table&gt; &lt;?php //Determine if a player as aligned three of its symbols and return the id of the player (1 //for X Player, -1 for O Player(Computer)). Otherwise return 0; function isWinState($board){ $winning_sequences = '012345678036147258048642'; for($i=0;$i&lt;=21;$i+=3){ $player = $board[$winning_sequences[$i]]; if($player == $board[$winning_sequences[$i+1]]){ if($player == $board[$winning_sequences[$i+2]]){ if($player!=0){ return $player; } } } } return 0; } //Player O plays its turn at random function OsTurn($board){ if(in_array(0,$board)){ $i = mt_rand(0,8); while($board[$i]!=0){ $i = mt_rand(0,8); } $board[$i]=-1; } return $board; } $winstate = 0; $values = array(); if(empty($_GET['values'])){ //initializing the board $values = array_fill(0,9,0); //determine who begins at random if(mt_rand(0,1)){ $values = OsTurn($values); } }else{ //get the board $values = explode(',',$_GET['values']); //Check if a player X won, if not, player 0 plays its turn. $winstate = isWinState($values); if($winstate==0){ $values = OsTurn($values); } //Check if a player 0 won $winstate = isWinState($values); } //Display the board as a table for($i=0;$i&lt;9;$i++){ //begin of a row if(fmod($i,3)==0){echo '&lt;tr&gt;';} echo '&lt;td&gt;'; //representation of the player token, depending on the ID if($values[$i]==1){ echo 'X'; }else if($values[$i]==-1){ echo 'O'; }else{ //If noone put a token on this, and if noone won, make a link to allow player X to //put its token here. Otherwise, empty space. if($winstate==0){ $values_link = $values; $values_link[$i]=1; echo '&lt;a href="tictactoe.php?values='.implode(',',$values_link).'"&gt;&amp;nbsp;&lt;/a&gt;'; }else{ echo '&amp;nbsp;'; } } echo '&lt;/td&gt;'; //end of a row if(fmod($i,3)==2){echo '&lt;/tr&gt;';} } ?&gt; &lt;/table&gt; &lt;?php //If someone won, display the message if($winstate!=0){ echo '&lt;p&gt;&lt;b&gt;Player '.(($winstate==1)?'X':'O').' won!&lt;/b&gt;&lt;/p&gt;'; } ?&gt; </code></pre>

366

<p>In our console app, the parsing of application arguments is done like so:</p> <pre><code>using System.Linq; namespace Generator { internal class Program { public static void Main(string[] args) { var param1 = args.SingleOrDefault(arg =&gt; arg.StartsWith("p1:")); if (!string.IsNullOrEmpty(param1)) { param1 = param1.Replace("p1:", ""); } //... } } } </code></pre> <p>It's supposed to be called like this:</p> <blockquote> <pre><code>`Generator.exe p1:somevalue` </code></pre> </blockquote> <p>Is there a better/simpler way to parse arguments?</p>

369

<p>Here is the skeleton of my (first!) Django app:</p> <pre><code># models.py class Task(models.Model): description = models.CharField(max_length = 200) ... # forms.py class AddTaskForm(forms.ModelForm): class Meta: model = Task </code></pre> <p>I then created two views using <code>AddTaskForm</code>: one to create a new instance, the other to edit an existing one. I was able to refactor those two views (and the function they call) into one, but I'm not sure I got the best possible result...</p> <pre><code># urls.py: (r'^yata/add_task/$', 'yata.views.edit'), (r'^yata/(?P&lt;task_id&gt;\d+)/edit/$', 'yata.views.edit'), # views.py def edit(request, task_id = None): t = get_object_or_404(Task, pk=task_id) if task_id else None if request.method == 'POST': form = AddTaskForm(request.POST, instance=t) if form.is_valid(): form.save() return HttpResponseRedirect('/yata/') else: form = AddTaskForm(instance = t) # Either the form was not valid, or we've just created it d = {'form': form} if task_id: # The template needs the id to decide if the form's action # is .../add_task or .../{{id}}/edit d['id'] = t.id return render_to_response('yata/edit.html', d, context_instance=RequestContext(request)) </code></pre> <p>And here is the corresponding part of the template:</p> <pre><code># edit.html {% if id %} &lt;form action="/yata/{{ id }}/edit/" method="post"&gt; {% else %} &lt;form action="/yata/add_task/" method="post"&gt; {% endif %} {{ form.as_p }} &lt;input type="submit" value="Save!" /&gt; &lt;/form&gt; </code></pre> <p>Is there a better Django idiom to handle this 'add or create' issue? Or can this be considered a correct way?</p>

374

<p><strong>Goal:</strong> To create a countdown to our next available live stream.</p> <p><strong>Details:</strong> We live stream six times a week all (PST). 1. Sunday at 8:00 a.m. 2. Sunday at 10:00 a.m. 3. Sunday at 12:00 p.m. 4. Sunday at 6:30 p.m. 5. Wednesday at 7:00 p.m. 6. Saturday at 10:00 a.m.</p> <p><strong>My approach:</strong> I check what day it is and what time it is then create the countdown to the next stream. </p> <p>I'm sure what I have done can be cleaned up and improved, so tell me how.</p> <pre><code>&lt;?php // Countdown Stuff $year = date(Y); $month = date(m); $month_day = date(d); $day = date(w); $hour = date(G); $min = date(i); $addDay = 0; // It's Sunday if ( $day == 0 ) { if ( $hour &lt; 8 ) { $hour = 8; $min = 0; } else if ( $hour &lt; 10 ) { $hour = 10; $min = 0; } else if ( $hour &lt; 12 ) { $hour = 12; $min = 0; } else if ( $hour &lt;= 18 &amp;&amp; $min &lt; 30 ) { $hour = 18; $min = 30; } else { $addDay = 3; $hour = 19; $min = 0; } } // It's Monday else if ( $day == 1 ) { $addDay = 2; $hour = 19; $min = 0; } // It's Tuesday else if ( $day == 2 ) { $addDay = 1; $hour = 19; $min = 0; } // It's Wednesday else if ( $day == 3) { if ( $hour &lt; 19 ) { $hour = 19; $min = 0; } else { $addDay = 3; $hour = 10; $min = 0; } } // It's Thursday else if ( $day == 4 ) { $addDay = 2; $hour = 10; $min = 0; } // It's Friday else if ( $day == 5 ) { $addDay = 1; $hour = 10; $min = 0; } // All that's left is Saturday else { if ( $hour &lt; 10 ) { $hour = 10; $min = 0; } else { $addDay = 1; $hour = 8; $min = 0; } } $build_date = $year . '-' . $month . '-' . $month_day . ' ' . $hour . ':' . $min . ':00'; $date = new DateTime($build_date); if ( $addDay ) { $date-&gt;modify("+$addDay day"); } $date = strtotime($date-&gt;format("Y-m-d G:i:s")); $now = strtotime("now"); $count = $date - $now; ?&gt; &lt;script type="text/javascript"&gt; var myTime = &lt;?=$count?&gt;; $('#countdown').countdown({ until: myTime}); &lt;/script&gt; </code></pre>

383

<p>I would like to solicit advice on everyone's thoughts on how best to combat the <a href="http://en.wikipedia.org/wiki/Anemic_Domain_Model" rel="nofollow">Anemic Domain Model anti-pattern</a> when building out a system based on web services.</p> <p>One of our goals is to build a set of core web services that expose the most basic services we reuse repeatedly in our organization, which is the creating of domain models. Right now we have a small library that we share and reuse but as we grow our team it would be much nicer to centralize these basic services. Over time our systems are going to change as some of the data may come from the cloud (Salesforce.com or AWS) so we're <strong>not just isolating basic DAO code in a web service but also application integration</strong>.</p> <p>For example, our customer data comes from the accounting, CRM, and order processing systems. Configuration is a real pain because every app that ships needs to be bundled with the core library and configuration on each system. I would like to centralize the creation of models, ala, SOA, but retain a rich model higher up in the Service Layer / Facade.</p> <p>If you think in general that this is a bad I'd be interested in hearing why!</p> <p>My thought is to define a domain object <code>Employee</code> that has an <code>EmployeeService</code> injected. At runtime the <code>EmployeeService</code> implementation is an <code>EmployeeWebServiceClientImpl</code> that implements said interface. <code>EmployeeWebServiceClientImpl</code> uses a web service proxy to the server.</p> <p>On the server-side of the web service we have <code>EmployeeWebService</code> invoking <code>EmployeeDao</code> to query the database. Could just as easily be a class calling out to Salesforce.com to get data. We would share a library that contained the domain model and interface so you would deserialize the web service response directly into a class that contained the needed business logic.</p> <p>Below is some example code in order from client to server:</p> <pre><code>//Example of client public static void main(String[] args) { try { Employee employee = Employee.getEmployee("james"); if (employee.isEligibleForRaise()) { System.out.println("Give that man a raise!"); } } catch (RuntimeException e) { System.out.println("Oh no!"); } } //Employee Domain Object public class Employee { private String name; private String username; private static EmployeeService service; public static Employee getEmployee(String username) { return service.getEmployee(username); } public static List&lt;Employee&gt; getAllEmployees() { return service.getAllEmployees(); } public boolean isEmployeeEligibleForRaise() { //business logic here return true; } //Getters &amp; Setters ... } //EmployeeWebServiceClientImpl public class EmployeeWebServiceClientImpl implements EmployeeService { //A client web service proxy to our core basic services BaseWebServiceProxy proxy; @Override public Employee getEmployee(String username) { return proxy.getEmployee(username); } @Override public List&lt;Employee&gt; getAllEmployees() { return proxy.getAllEmployees(); } } //On the server-side we have EmployeeWebService public class EmployeeWebService implements EmployeeService { EmployeeDao employeeDao; @Override public List&lt;Employee&gt; getAllEmployees() { return employeeDao.getAllEmployees(); } @Override public Employee getEmployee(String username) { return employeeDao.getEmployee(username); } } </code></pre> <p>Is that making sense? Basically the plan is to keep core business logic in the <code>Employee</code> domain object but isolate the data access logic in a web service.</p> <p>Thoughts?</p>

395

<p>I've made a SPL-based class named "Recordset" that wraps both MySQLi_STMT and MySQLi_Result objects and allows treating either as a 3-dimensional array. It requires PHP5.3+.</p> <p>I'm pretty bummed about the slow foreach loop over my Recordset object, by the slower internal seek and fetch speeds within Recordset, and by the fact that nothing can even compare to the old <code>while ($MySQLI_STMT-&gt;fetch()) {}</code>. I've already cached certain result information, such as num_rows and class name, and try to avoid chaining internal function calls, which speeds things up considerably. Unfortunately, this cuts down on proper internal data validation checks. The constant data_seek calls do slow things a little. I'd like for this to work better. Any suggestions or insight how to speed up foreach loops and internal row fetching?</p> <p>Here's excerpts of the important parts...</p> <pre><code>class Recordset implements Iterator, ArrayAccess, Countable { private $MySQLi_set; // MySQLi_STMT or MySQLi_Result object private $MySQLi_set_type; // cache of MySQLi_STMT or MySQLi_Result object type to avoid repeat instanceof calls private $field_metadata; // array of field info objects returned by query private $num_rows; // cache row count to avoid repeat mysqli_x-&gt;num_rows call private $bind_row; // binding array for MySQLi_STMT results private $pointer; // for tracking iterations over records in query function __construct($sql) { $bind_params = func_get_args(); array_shift($bind_params); try { if (count($bind_params) === 0) { // expecting MYSQLI_Result obj returned, replace code as necessary $this-&gt;MySQLi_set = DB_Main::query($sql); } else { // expecting MySQLi_STMT obj returned, replace code as necessary $this-&gt;MySQLi_set = DB_Main::statement($sql, $bind_params); } } catch (Exception $e) { throw new RuntimeException(((count($bind_params)) ? 'Statement' : 'Query') . ' failed: ' . $e-&gt;getMessage(), $e-&gt;getCode(), $e); } // cache name of object to avoid repeat instanceof calls $this-&gt;MySQLi_set_type = get_class($this-&gt;MySQLi_set); if ($this-&gt;MySQLi_set_type === 'mysqli_result') { // set $this-&gt;field_metadata to array of field info objects $this-&gt;field_metadata = $this-&gt;MySQLi_set-&gt;fetch_fields(); } else if ($this-&gt;MySQLi_set_type === 'mysqli_stmt') { // Set up special handling for MySQLi_STMT objects // set $this-&gt;field_metadata to array of field info objects used later for result bindings for MySQLi_STMT object $result_metadata = $this-&gt;MySQLi_set-&gt;result_metadata(); $this-&gt;field_metadata = $result_metadata-&gt;fetch_fields(); $result_metadata-&gt;free_result(); unset($result_metadata); // store results to allow object to act as a countable, seekable array if (!$this-&gt;MySQLi_set-&gt;store_result()) throw new RuntimeException('MySQLi_STMT Result failed to store. Error: ' . $this-&gt;MySQLi_set-&gt;error); // because bind_result() cannot bind to an object or array, use the 'call_user_func_array()' technique instead $this-&gt;bind_row = array(); $bind_row2 = array(); foreach($this-&gt;field_metadata as $field) $bind_row2[$field-&gt;name] =&amp; $this-&gt;bind_row[$field-&gt;name]; if (!call_user_func_array(array($this-&gt;MySQLi_set, 'bind_result'), $this-&gt;bind_row)) throw new RuntimeException($this-&gt;MySQLi_set-&gt;error); if ($this-&gt;MySQLi_set-&gt;error) throw new RuntimeException($this-&gt;MySQLi_set-&gt;error); } else { throw new RuntimeException('No MySQLi_STMT or MySQLi_Result object to work with. Class: ' . $this-&gt;MySQLi_set_type . ' attempted.'); } // cache row count to avoid constant calls to MySQLi_x-&gt;num_rows $this-&gt;num_rows = $this-&gt;MySQLi_set-&gt;num_rows; // if rows were returned, set internal pointer to 0 if ($this-&gt;num_rows &gt; 0) $this-&gt;pointer = 0; } function fetchRow($offset = null) { // private function internally using regular fetch() methods to progress through records // sets $this-&gt;bind_row to an associative array of the next record for MySQLi_STMT wrapped objects $this-&gt;MySQLi_set-&gt;data_seek((($offset !== null) ? (int) $offset : $this-&gt;pointer)); if ($this-&gt;MySQLi_set_type === 'mysqli_result') return $this-&gt;MySQLi_set-&gt;fetch_assoc(); // else this is a MySQLi_STMT object $fetch_status = $this-&gt;MySQLi_set-&gt;fetch(); if ($fetch_status === true) return $this-&gt;bind_row; else if ($fetch_status === null) return null; // no more rows // MySQLi_STMT row fetch failed throw new RuntimeException('Error fetching row: . ' . $this-&gt;MySQLi_set-&gt;error); } function count() {return $this-&gt;num_rows;} function current() {return $this-&gt;fetchRow();} function key() {return $this-&gt;pointer;} function next() {$this-&gt;pointer++;} function rewind() {$this-&gt;pointer = 0;} function valid() {return $this-&gt;offsetExists($this-&gt;pointer);} function offsetExists($offset) { // Part of the ArrayAccess interface. Used to determine if the selected record in the set actually exists or is out of bounds. // Example: 'isset($Recordset[22])' returns true if there were 23 or more records returned from the query. return ((int) $offset &lt; $this-&gt;num_rows AND (int) $offset &gt;= 0); } function offsetGet($offset) { // Part of the ArrayAccess interface. Used to retrieve the assoc array of the chosen record in line. // allow index referencing without altering "internal array pointer" // Example: 'print_r($Recordset[22])' prints the 23rd record returned by the query. if (!((int) $offset &lt; $this-&gt;num_rows AND (int) $offset &gt;= 0)) throw new OutOfBoundsException('Out of range of result set.'); return $this-&gt;fetchRow($offset); } } </code></pre> <p>The code is roughly 200 lines long, so instead of making a giant post, here's a pastebin link... <a href="http://pastebin.com/n17MuEzf" rel="noreferrer">http://pastebin.com/n17MuEzf</a></p> <p><b>Use...</b></p> <p>Objects are created by passing in an sql query string. For handling prepared statements, simply pass in additional arguments as the prepared binding parameters. In those cases, there is a behind-the-scenes <code>bind_param</code> going on generating the MySQLi_STMT object to be wrapped. That part isn't included here, so for the purposes of this post, pretend it's magic.</p> <p>For example to automatically handle the query as a prepared statement and output rows:</p> <pre><code>$recordset = new Recordset("SELECT * FROM tblComments WHERE(parentBlogID = ?)", 2); if (count($recordset) &gt; 0) { foreach ($recordset as $record) echo $record['commentText'] . '&lt;br&gt;'; } else echo "No records returned."; </code></pre> <p><b>Advantages...</b></p> <ul> <li>Allows accessing result rows by array key (<code>echo $Recordset[295]['title'];</code>) or by foreach loops (<code>foreach ($Recordsetas $rec) {echo $rec['title'];}</code>).</li> <li>Allows you to get a row by index number without interfering with the internal result pointer. In other words, right in the middle of a foreach loop, you can do <code>$x = $Recordset[259]['ID'];</code> without causing the internal result row pointer to jump out of order.</li> <li>Allows exchanging this class out for regular 3-dimensional arrays of result dumps.</li> <li>Avoids duplication of result binding code for every statement throughout an application.</li> <li>Lets you still access functions and properties of the wrapped MySQLi object directly (<code>$Recordset->attr_get(1)</code>).</li> <li>Would allow plugging in automatic output filters or template handling.</li> </ul> <p><b>Tests...</b></p> <p>Here's some speed tests iterating over 10000 records from a localhost table with 6 columns. This test was done with prepared statement results either wrapped in Recordset or not. Timing is measured starting before and ending after each entire loop call..</p> <p><b>With Recordset...</b></p> <ul> <li><code>foreach($Recordset as $rec) {$x = $rec;}</code> ... <br> 0.1033s</li> <li><code>for ($i = 0, $count = count($Recordset); $i &lt; $count; $i++) {$x = $Recordset[$i];}</code> ... <br> 0.0445s</li> <li><code>for ($i = 0, $count = count($Recordset); $i &lt; $count; $i++) {$x = $Recordset-&gt;fetchRow($i);}</code> ... <br> 0.0344 s</li> <li><code>while ($x = $Recordset[$i]) {$i++; if (!isset($Recordset[$i])) break;}</code> ... <br> 0.0542 s</li> </ul> <p><b>Without Recordset, but still using the "bind to array" technique and pre-storing results...</b></p> <ul> <li><code>for ($i=0, $count=MySQLI_STMT-&gt;num_rows; $i &lt; $count; $i++)) {$MySQLI_STMT-&gt;fetch(); $x = $bind_row;}</code> ...<br> 0.0414 s</li> <li><code>while ($MySQLI_STMT-&gt;fetch()) {$x = $bind_row;}</code> ... <br> 0.009 s</li> </ul>

401

<p>Theme-swap functionality will be done via a better-looking <code>&lt;div&gt;</code> at the top of the page, but for right now, it's just thrown on the button. The theme preference should persist through page refreshes through the use of cookies. </p> <p>I'm going to do five different themes, each in two different sizes, since the site is very bad in <code>800x600</code> and still quite bad in <code>1024x768</code>.</p> <p>Let me know if it breaks or simply doesn't work. I've noticed a bug that happens once in a blue moon, but I think that's because the browser might be doing parallel work and one script gets too far ahead of the other. I'll have to research it more, but I think it's good enough right now to ask for opinions.</p> <p>The page will eventually display via <code>&lt;noscript&gt;</code> for those that don't have JavaScript turned on but for right now, it'll just display a message that says:</p> <blockquote> <p>Please turn JavaScript on!</p> </blockquote> <p>How it works:</p> <ol> <li>Non-JavaScript page is displayed with <code>&lt;noscript&gt;</code></li> <li>If JavaScript is enabled, it loads the theme-preference from cookies.</li> <li>JavaScript then applies the preferred theme via AJAX fetching the appropriate theme (<code>skin[x].html</code>) and the content of the page (<code>[page_name.html]</code>).</li> </ol> <p>The code isn't perfect yet, and I'll definitely have to remove the use of another person's image as the background for the second skin, but it's almost done. About half of the code deals with merely re-positioning the elements when the window is resized. For the sake of brevity, some code is not shown. I apologize for its length.</p> <h3>index.html:</h3> <pre><code>&lt;script type="text/javascript"&gt; window.onresize = function() { setContentPositions(); setJSMenuPositions(); } $('html').addClass('js'); &lt;/script&gt; &lt;script type="text/javascript"&gt; $().ready(function() { getThemeInfo(); AJAX_LoadResponseIntoElement("mybody", "skin1.txt", function() { AJAX_LoadResponseIntoElement("contentdiv", "index.txt", initPage); }); if (themeSelect&gt;1) { themeSwapNoInc();} }); &lt;/script&gt; </code></pre> <h3>funcs.js:</h3> <pre><code>function getThemeInfo() { themeSelect=checkCookie(); } function themeSwap() { themeSelect++; if (themeSelect&gt;2 || themeSelect&lt;1) {themeSelect=1;} $('html').addClass('js'); switch(themeSelect) { case 1: AJAX_LoadResponseIntoElement("mybody", "skin1.txt", function() { AJAX_LoadResponseIntoElement("contentdiv", "index.txt", initPage); }); document.body.style.backgroundImage="url(http://www.solarcoordinates.com/images/bg2b.png)"; document.body.style.backgroundRepeat="repeat-x"; break; case 2: AJAX_LoadResponseIntoElement("mybody", "skin2.txt", function() { AJAX_LoadResponseIntoElement("contentdiv", "index.txt", initPage); }); document.body.style.backgroundImage="url(http://www.constantcollide.com/wp-content/themes/killerbrown/images/texture.jpg)"; document.body.style.backgroundRepeat="repeat"; break; } setCookie("themeSelection",themeSelect,365); } function themeSwapNoInc() { themeSelect--; themeSwap(); } function initPage() { $('#vertnav .kwicks').kwicks({ defaultKwick:0, max : 205, spacing : 3, isVertical : true }); setContentPositions(); replaceCSSMenu(); showContainer(); setJSMenuPositions(); } function showContainer() { $('html').removeClass('js'); } function AJAX_LoadResponseIntoElement (elementId, fetchFileName, cfunc) { var XMLHRObj; if (window.XMLHttpRequest) { XMLHRObj=new XMLHttpRequest(); } else { XMLHRObj=new ActiveXObject("Microsoft.XMLHTTP"); } XMLHRObj.onreadystatechange=function() { if (XMLHRObj.readyState==4 &amp;&amp; XMLHRObj.status==200) { document.getElementById(elementId).innerHTML=XMLHRObj.responseText; cfunc(); } } XMLHRObj.open("GET",fetchFileName,true); XMLHRObj.send(); } function findLeft(obj) { var curleft = 0; if (obj.offsetParent) { do {curleft += obj.offsetLeft;} while (obj = obj.offsetParent);} else { curleft += obj.offsetLeft; } return curleft; } function findTop(obj) { var curtop = 0; if (obj.offsetParent) { do {curtop += obj.offsetTop;} while (obj = obj.offsetParent);} else { curtop += obj.offsetTop; } return curtop; } function findmyparent(e) { var srcElement = e.srcElement ? e.srcElement : e.target; if (srcElement.className.search("jsmenu")==-1 &amp;&amp; srcElement.className.search("kwick")==-1 &amp;&amp; srcElement.className!="vertnav" &amp;&amp; srcElement.className!="active") { document.getElementById("jsmenu" + lastindex).style.display="none"; submenuvisible=false; } } function getContentHeight() { return window.innerHeight; } function getContentWidth() { return window.innerWidth; } function setContentPositions() { var DOMheight = getContentHeight()? getContentHeight(): window.document.body.parentElement.clientHeight; var DOMwidth = getContentWidth()? getContentWidth(): window.document.body.parentElement.clientWidth; var y_lbound, x_lbound, x_ubound; var container_ymod, container_ymin; var container_xmod, container_xmax, container_xmin; var content_xmod, content_xmax, content_xmin; switch (themeSelect) { case 1: y_lbound=727; x_lbound=910; x_ubound=1400; container_ymod=-240; container_ymin=487; container_xmod=-240; container_xmax=1160; container_xmin=670; content_xmod=-490; content_xmax=910; content_xmin=420; break; case 2: y_lbound=710; x_lbound=910; x_ubound=1400; container_ymod=-178; container_ymin=532; container_xmod=-300; container_xmax=1100; container_xmin=610; content_xmod=-350; content_xmax=1050; content_xmin=560; break; default: } // end switch if (DOMheight &gt; y_lbound) { document.getElementById('containerdiv').style.height = (DOMheight+container_ymod) + 'px'; } else { document.getElementById('containerdiv').style.height = container_ymin + 'px'; } if (DOMwidth &gt; x_lbound) { if (DOMwidth &lt; x_ubound) { document.getElementById('containerdiv').style.width = (DOMwidth+container_xmod) + 'px'; document.getElementById('contentdiv').style.width = (DOMwidth+content_xmod) + 'px'; } else { document.getElementById('containerdiv').style.width = container_xmax +'px'; document.getElementById('contentdiv').style.width = content_xmax + 'px'; } } else { document.getElementById('containerdiv').style.width = container_xmin + 'px'; document.getElementById('contentdiv').style.width = content_xmin + 'px'; } } </code></pre> <h3>jsmenucontent.js:</h3> <pre><code>function setJSMenuPositions() { var popupleft = findLeft(document.getElementById('kwick1'))+168; var popuptop = findTop(document.getElementById('kwick1')); document.getElementById('jsmenu0').style.left = popupleft + "px"; document.getElementById('jsmenu0').style.top = popuptop -12+ "px"; document.getElementById('jsmenu1').style.left = popupleft + "px"; document.getElementById('jsmenu1').style.top = popuptop +33+ "px"; document.getElementById('jsmenu2').style.left = popupleft + "px"; document.getElementById('jsmenu2').style.top = popuptop +77+ "px"; } </code></pre>

403

<p>I'm thinking about how to do a color transition for a line in WPF. I'm looking for this to be as simple and succinct as possible, and also the "correct" way in the WPF world.</p> <p>This is what I have, taking the line from it's previous color to <code>Colors.LightGreen</code> in 0.1 seconds.</p> <pre><code>Line TargetLine = GetMyTargetLine(); var s = new Storyboard(){ Duration = new Duration(TimeSpan.FromSeconds(0.1f)) }; s.Children.Add(new ColorAnimation(Colors.LightGreen, s.Duration)); Storyboard.SetTarget(s.Children[0], TargetLine); Storyboard.SetTargetProperty(s.Children[0], new PropertyPath("Stroke.Color")); s.Begin(); </code></pre> <p>And it is functional. Is this the proper way to do it in the WPF mindset? It just seems very clunky and verbose way to express what I want to do. Thoughts?</p> <p><strong>Edit:</strong> With Snowbear's advice I can at least get it to 4 lines. The entire context of the storyboard is right here so I don't think it's a big deal to reference the only child by index. If it were any more complex than this I'd agree that it should be a named variable.</p> <pre><code> Line TargetLine = GetMyTargetLine(); var story = new Storyboard() { Children = { new ColorAnimation(color, new Duration(TimeSpan.FromSeconds(0.1))) } }; Storyboard.SetTarget(story.Children[0], TargetLine); Storyboard.SetTargetProperty(story.Children[0], new PropertyPath("Stroke.Color")); story.Begin(); </code></pre>

404

<p>Consider the following method that I have for checking write permissions on a directory path:</p> <pre><code>/// &lt;summary&gt; /// Check existence and write permissions of supplied directory. /// &lt;/summary&gt; /// &lt;param name="directory"&gt;The directory to check.&lt;/param&gt; protected static void CheckPermissions(string directory) { if (!Directory.Exists(directory)) { throw new DirectoryNotFoundException(String.Format(JobItemsStrings.Job_DirectoryNotFound, directory)); } // Check permissions exist to write to the directory. // Will throw a System.Security.SecurityException if the demand fails. FileIOPermission ioPermission = new FileIOPermission(FileIOPermissionAccess.Write, directory); ioPermission.Demand(); } </code></pre> <p>When running FxCop, this code throws up a <strong>"CA2103 - Review imperative security"</strong> warning, albeit with a certainty of 25%, with this info:</p> <blockquote> <p>"Use of imperative demands can lead to unforeseen security problems. The values used to construct a permission should not change within the scope of the demand call. For some components the scope spans from the demand call to end of the method; for others it spans from the demand call until the component is finalized. If the values used to construct the permission are fields or properties, they can be changed within the scope of the demand call. This can lead to race conditions, mutable read-only arrays, and problems with boxed value types."</p> </blockquote> <p>Bascially, is FxCop being over-cautious, or am I doing it wrong?</p>

413

<p>I have a stored procedure that looks up an article based on the article's title. But I also need to increment a column in the same table that counts the number of times the article has been viewed.</p> <p>Trying to be as efficient as possible, I wanted a way to do this without performing multiple lookups. Someone pointed out the newer OUTPUT clause, which I've used below.</p> <p>I'm just wondering if I'm using it in the most efficient way, if I really made it faster, and if there are any other optimizations that could be employed.</p> <pre><code>DECLARE @Slug VARCHAR(250) -- Stored procedure argument -- declare @UpdatedArticle table variable DECLARE @UpdatedArticle TABLE ( ArtID INT, ArtUserID UNIQUEIDENTIFIER, ArtSubcategoryID INT, ArtTitle VARCHAR(250), ArtHtml VARCHAR(MAX), ArtDescription VARCHAR(350), ArtKeywords VARCHAR(250), ArtLicenseID VARCHAR(10), ArtViews BIGINT, ArtCreated DATETIME2(7), ArtUpdated DATETIME2(7) ); UPDATE Article SET ArtViews = ArtViews + 1 OUTPUT INSERTED.ArtID, INSERTED.ArtUserID, inserted.ArtSubcategoryID, INSERTED.ArtTitle, INSERTED.ArtHtml, INSERTED.ArtDescription, INSERTED.ArtKeywords, INSERTED.ArtLicenseID, INSERTED.ArtViews, INSERTED.ArtUpdated, INSERTED.ArtCreated INTO @UpdatedArticle WHERE ArtSlugHash = CHECKSUM(@Slug) AND ArtSlug = @Slug AND ArtApproved = 1 SELECT a.ArtID, a.ArtUserID, a.ArtTitle, a.ArtHtml, a.ArtDescription, a.ArtKeywords, a.ArtLicenseID, l.licTitle, a.ArtViews, a.ArtCreated, a.ArtUpdated, s.SubID, s.SubTitle, c.CatID, c.CatTitle, sec.SecID, sec.SecTitle, u.UsrDisplayName AS UserName FROM @UpdatedArticle a INNER JOIN Subcategory s ON a.ArtSubcategoryID = s.SubID INNER JOIN Category c ON s.SubCatID = c.CatID INNER JOIN [Section] sec ON c.CatSectionID = sec.SecID INNER JOIN [User] u ON a.ArtUserID = u.UsrID INNER JOIN License l ON a.ArtLicenseID = l.LicID </code></pre> <p>This is used in an ASP.NET application using SQL Server 2008.</p>

415

<p>This system has to manage students, teachers, staff and grading. This is for production and is not a school assignment. As such, please let me know if I can improve on any aspect. :)</p> <p>My main concern is automation. I'd like my software to be able to run regardless if I still exist. </p> <p>I'm using SQLite as the database:</p> <pre><code>create table User ( ID integer primary key autoincrement, Username string, Password string ); create table Area ( ID integer primary key autoincrement, Name string ); create table Subject ( ID integer primary key autoincrement, Name string, Abbreviation string, IDArea integer references Area(ID) ); create table Level ( ID integer primary key autoincrement, Name string, Principle string ); create table Grade ( ID integer primary key autoincrement, Name string, IDLevel integer references Level(ID), Observation string ); create table StaffType ( ID integer primary key autoincrement, Name string ); create table Staff ( ID integer primary key autoincrement, IDStaffType integer references StaffType(ID), Name string, LastNameFather string, LastNameMother string, DateOfBirth string, PlaceOfBirth string, Sex string, Carnet string, Telephone string, MobilePhone string, Address string, FatherName string, MotherName string, FatherContact string, MotherContact string, FatherPlaceOfWork string, MotherPlaceOfWork string, DateOfHiring string, YearsOfService string, Formation string, Specialty string, Category string, Salary string ); create table GradeParalelo ( ID integer primary key autoincrement, IDGrade integer references Grade(ID), IDStaff integer references Staff(ID), Name string ); create table Student ( ID integer primary key autoincrement, IDGradeParalelo integer references GradeParalelo(ID), Rude string, Name string, LastNameFather string, LastNameMother string, DateOfBirth string, PlaceOfBirth string, Sex string, Carnet string, Telephone string, MobilePhone string, Address string, FatherName string, MotherName string, FatherMobilePhone string, MotherMobilePhone string, FatherProfession string, MotherProfession string, FatherPlaceOfWork string, MotherPlaceOfWork string, Observations string ); create table Attendance ( ID integer primary key autoincrement, IDStudent integer references Student(ID), Attended string, Date string ); create table SubjectGrade ( ID integer primary key autoincrement, IDGrade integer references Grade(ID), IDSubject integer references Subject(ID) ); create table ScoreRecord ( ID integer primary key autoincrement, IDSubject integer references Subject(ID), IDStudent integer references Student(ID), FirstTrimester integer, SecondTrimester integer, ThirdTrimester integer, FinalGrade integer, Year string ); </code></pre> <p><a href="https://i.stack.imgur.com/gUAbT.jpg" rel="noreferrer"><img src="https://i.stack.imgur.com/gUAbT.jpg" alt="Entity/Relationship diagram"></a></p> <p>Any glaring room for improvement?</p>

418

<p>While researching ways to convert back and forth between <code>std::wstring</code> and <code>std::string</code>, I found <a href="http://social.msdn.microsoft.com/Forums/en/Vsexpressvc/thread/0f749fd8-8a43-4580-b54b-fbf964d68375">this conversation</a> on the MSDN forums.</p> <p>There were two functions that, to me, looked good. Specifically, these:</p> <pre><code>std::wstring s2ws(const std::string&amp; s) { int len; int slength = (int)s.length() + 1; len = MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, 0, 0); wchar_t* buf = new wchar_t[len]; MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, buf, len); std::wstring r(buf); delete[] buf; return r; } std::string ws2s(const std::wstring&amp; s) { int len; int slength = (int)s.length() + 1; len = WideCharToMultiByte(CP_ACP, 0, s.c_str(), slength, 0, 0, 0, 0); char* buf = new char[len]; WideCharToMultiByte(CP_ACP, 0, s.c_str(), slength, buf, len, 0, 0); std::string r(buf); delete[] buf; return r; } </code></pre> <p>However, the double allocation and the need to delete the buffer concern me (performance and exception safety) so I modified them to be like this:</p> <pre><code>std::wstring s2ws(const std::string&amp; s) { int len; int slength = (int)s.length() + 1; len = MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, 0, 0); std::wstring r(len, L'\0'); MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, &amp;r[0], len); return r; } std::string ws2s(const std::wstring&amp; s) { int len; int slength = (int)s.length() + 1; len = WideCharToMultiByte(CP_ACP, 0, s.c_str(), slength, 0, 0, 0, 0); std::string r(len, '\0'); WideCharToMultiByte(CP_ACP, 0, s.c_str(), slength, &amp;r[0], len, 0, 0); return r; } </code></pre> <p>Unit testing indicates that this works in a nice, controlled environment but will this be OK in the vicious and unpredictable world that is my client's computer?</p>

419

<p>Having coded in Java and C# for quite some years, I'm currently learning Ruby. I'm working my way through the <a href="http://rubykoans.com/" rel="noreferrer">Ruby Koans tutorial</a>. At some point, you are to implement a method that calculates the game-score of a dice-game called Greed.</p> <p>I came up with this recursive Java/C#-like method. It passes all the supplied unit tests, so technically it's correct. </p> <p>Now I'm wondering: Is this good Ruby code? If not, how would a "Rubyist" write this method? And possibly: Why? I'm also not so happy about the amount of duplicate code but can't think of a better Rubyish way.</p> <pre><code>def score(dice) #dice is an array of numbers, i.e. [3,4,5,3,3] return 0 if(dice == [] || dice == nil) dice.sort! return 1000 + score(dice[3..-1]) if(dice[0..2] == [1,1,1]) return 600 + score(dice[3..-1]) if(dice[0..2] == [6,6,6]) return 500 + score(dice[3..-1]) if(dice[0..2] == [5,5,5]) return 400 + score(dice[3..-1]) if(dice[0..2] == [4,4,4]) return 300 + score(dice[3..-1]) if(dice[0..2] == [3,3,3]) return 200 + score(dice[3..-1]) if(dice[0..2] == [2,2,2]) return 100 + score(dice[1..-1]) if(dice[0] == 1) return 50 + score(dice[1..-1]) if(dice[0] == 5) return 0 + score(dice[1..-1]); end </code></pre> <p><strong>Some background (if needed)</strong></p> <pre><code># Greed is a dice game where you roll up to five dice to accumulate # points. A greed roll is scored as follows: # # * A set of three ones is 1000 points # # * A set of three numbers (other than ones) is worth 100 times the # number. (e.g. three fours is 400 points). # # * A one (that is not part of a set of three) is worth 100 points. # # * A five (that is not part of a set of three) is worth 50 points. # # * Everything else is worth 0 points. # # # Examples: # # score([1,1,1,5,1]) =&gt; 1150 points # score([2,3,4,6,2]) =&gt; 0 points # score([3,4,5,3,3]) =&gt; 350 points # score([1,5,1,2,4]) =&gt; 250 points # # More scoring examples are given in the tests below: class AboutScoringProject &lt; EdgeCase::Koan def test_score_of_an_empty_list_is_zero assert_equal 0, score([]) end def test_score_of_a_single_roll_of_5_is_50 assert_equal 50, score([5]) end def test_score_of_a_single_roll_of_1_is_100 assert_equal 100, score([1]) end def test_score_of_a_single_roll_of_1_is_100 assert_equal 200, score([1,1]) end def test_score_of_multiple_1s_and_5s_is_the_sum_of_individual_scores assert_equal 300, score([1,5,5,1]) end def test_score_of_single_2s_3s_4s_and_6s_are_zero assert_equal 0, score([2,3,4,6]) end def test_score_of_a_triple_1_is_1000 assert_equal 1000, score([1,1,1]) end def test_score_of_other_triples_is_100x assert_equal 200, score([2,2,2]) assert_equal 300, score([3,3,3]) assert_equal 400, score([4,4,4]) assert_equal 500, score([5,5,5]) assert_equal 600, score([6,6,6]) end def test_score_of_mixed_is_sum assert_equal 250, score([2,5,2,2,3]) assert_equal 550, score([5,5,5,5]) end def test_score_of_a_triple_1_is_1000A assert_equal 1150, score([1,1,1,5,1]) end def test_score_of_a_triple_1_is_1000B assert_equal 350, score([3,4,5,3,3]) end def test_score_of_a_triple_1_is_1000C assert_equal 250, score([1,5,1,2,4]) end end </code></pre>

423

<p>I have been developing this class, and was wondering if anyone had any thoughts on how I can improve the performance of it.</p> <pre><code>&lt;?php class Something { private $APIUsername, $APIPassword; private $APIurl = 'somesite.com'; function __construct ($APIUsername = '', $APIPassword = '') { try { if (!$APIUsername || !$APIPassword) { throw new Exception('You must specify a valid API username and password.'); } $this-&gt;APIUsername = $APIUsername; $this-&gt;APIPassword = $APIPassword; } catch (Exception $e) { die($e-&gt;getMessage()); } } /* * Authenticate Account */ public function authenticate ($EmailAddress, $Password) { try { $data['EmailAddress'] = $EmailAddress; $data['Password'] = $Password; $data = $this-&gt;setJSON($data); $result = $this-&gt;fetch('authenticate', $data); } catch (Exception $e) { $result = $e-&gt;getMessage(); } return $result; } /* * Get Contacts */ public function contacts ($EmailAddress, $Password, $PIN) { try { $data['EmailAddress'] = $EmailAddress; $data['Password'] = $Password; $data['PIN'] = $PIN; $data = $this-&gt;setJSON($data); $result = $this-&gt;fetch('contacts', $data); } catch (Exception $e) { $result = $e-&gt;getMessage(); } return $result; } /* * Get Transactions */ public function transactions ($EmailAddress, $Password, $PIN) { try { $data['EmailAddress'] = $EmailAddress; $data['Password'] = $Password; $data['PIN'] = $PIN; $data = $this-&gt;setJSON($data); $result = $this-&gt;fetch('transactions', $data); } catch (Exception $e) { $result = $e-&gt;getMessage(); } return $result; } /* * Validate PIN */ public function validatepin ($EmailAddress, $Password, $PIN) { try { $data['EmailAddress'] = $EmailAddress; $data['Password'] = $Password; $data['PIN'] = $PIN; $data = $this-&gt;setJSON($data); $result = $this-&gt;fetch('validatepin', $data); } catch (Exception $e) { $result = $e-&gt;getMessage(); } return $result; } /* * Get Account Balance */ public function balance ($EmailAddress, $Password) { try { $data['EmailAddress'] = $EmailAddress; $data['Password'] = $Password; $data = $this-&gt;setJSON($data); $result = $this-&gt;fetch('balance', $data); } catch (Exception $e) { $result = $e-&gt;getMessage(); } return $result; } /* * Get Account Information */ public function account_information ($EmailAddress, $Password) { try { $data['EmailAddress'] = $EmailAddress; $data['Password'] = $Password; $data = $this-&gt;setJSON($data); $result = $this-&gt;fetch('account_information', $data); } catch (Exception $e) { $result = $e-&gt;getMessage(); } return $result; } /* * Send Money */ public function send ($EmailAddress, $Password, $PIN, $DestinationID, $Amount, $Notes = '', $FundsSource = '') { try { $data['EmailAddress'] = $EmailAddress; $data['Password'] = $Password; $data['PIN'] = $PIN; $data['DestinationID'] = $DestinationID; $data['Amount'] = $Amount; $data['Notes'] = urlencode($Notes); $data['FundsSource'] = $FundsSource; $data = $this-&gt;setJSON($data); $result = $this-&gt;fetch('send', $data); } catch (Exception $e) { $result = $e-&gt;getMessage(); } return $result; } /* * Send (Sender Assumes Transaction Costs) */ public function send_assume_costs ($EmailAddress, $Password, $PIN, $DestinationID, $Amount, $Description = '') { try { $data['EmailAddress'] = $EmailAddress; $data['Password'] = $Password; $data['PIN'] = $PIN; $data['DestinationID'] = $DestinationID; $data['Amount'] = $Amount; $data['Description'] = urlencode($Description); $data = $this-&gt;setJSON($data); $result = $this-&gt;fetch('send_assume_costs', $data); } catch (Exception $e) { $result = $e-&gt;getMessage(); } return $result; } /* * Set JSON Data */ private function setJSON ($data) { $a = array(); $a['APIUsername'] = $this-&gt;APIUsername; $a['APIPassword'] = $this-&gt;APIPassword; foreach ($data as $key =&gt; $value) { $a[$key] = $value; } return json_encode($a); } /* * Helper method that talks to teh API */ private function fetch($APIMethod, $data) { $c = curl_init($this-&gt;APIurl.$APIMethod); curl_setopt($c, CURLOPT_SSL_VERIFYPEER, false); curl_setopt($c, CURLOPT_RETURNTRANSFER, 1); curl_setopt($c, CURLOPT_HTTPHEADER, array('Accept: application/json', 'Content-Type: application/json')); curl_setopt($c, CURLOPT_POSTFIELDS, $data); $returned = curl_exec($c); if ($returned === false) { throw new Exception(curl_error($c)); return; } curl_close($c); if (json_decode($returned)) { return $returned; } else { throw new Exception('Invalid Service Request.'); return; } } } ?&gt; </code></pre>

427

<p>I wrote the following little shell script and published it on <a href="https://github.com/Basphil/random-xkcd-wallpaper/" rel="nofollow" title="My github repo">GitHub</a>. In the repo there's also a README file that explains how to use it in more detail.</p> <p>This is the first time I open-sourced/published something I wrote, so I'm interested whether you think that this code is ready for the public. </p> <p>Some pointers, but feel free to add your own thoughts:</p> <ol> <li>Does it look professional? If not, what would need to be done?</li> <li>Are the comments too much? Was it ok to publish it, although I know that under some circumstances it doesn't work (I wrote about that in the README)?</li> </ol> <p></p> <pre><code># random xkcd wallpaper: gets a random xkcd comic from xkcd.com and sets it as the desktop background. #!/bin/bash # /random/comic redirects to random comic. Wget gets the index.html of the comic. wget http://dynamic.xkcd.com/random/comic/ echo $(pwd) #Searches the line in the index.html file that points to the url where the actual comic is placed. #The image urls are of the form: http://imgs.xkcd.com/comics/.'name of comic'.(png | jpg) url=$(cat index.html | grep -o -m 1 http://imgs.xkcd.com/comics/.*\.png) #Assuming picture format is .png. Gets the name of the image file by only matching what comes after the last forward slash. name_pic=$(echo $url | grep -o [^/]*\.png) is_png=1 #Sets url and name_pic in the case of the picture being in .jpg format. if [ -z "$url" ] then url=$(cat index.html | grep -o -m 1 http://imgs.xkcd.com/comics/.*\.jpg) name_pic=$(echo $url | grep -o [^/]*\.jpg) is_png=0 fi #Downloads the image and saves it under its appropriate name. wget --output-document="$name_pic" "$url" #Sets the desktop background gconftool-2 --set --type=string /desktop/gnome/background/picture_filename $(pwd)/"$name_pic" #Cleans up rm index.html #For some reason, if the image is moved to fast (e.g without a wait) the background does not get set. sleep 1 #The current wallpaper can always be found under "current_xkcd_wallpaper.png" or "current_xkcd_wallpaper.jpg". Also prevents cluttering the directory with images. #If you want to keep all the pictures you downloaded, uncomment the following lines. #Cleans up. Makes sure that there is only one current_xkcd_wallpaper image file. #rm current_xkcd_wallpaper.* rm current_xkcd_wallpaper.* if [ $is_png = 1 ] ; then mv $(pwd)/"$name_pic" $(pwd)/current_xkcd_wallpaper.png else mv $(pwd)/"$name_pic" $(pwd)/current_xkcd_wallpaper.jpg fi </code></pre>

428

<p>This weekend I've been having one heck of a time getting WPF Ribbon v4 working with MVVM and Prism (using unity). After much trial and error, I believe I have it working. I was hoping someone could take a look at it and give me some feedback.</p> <p>RibbonRegionAdapter.cs</p> <pre><code>public class RibbonRegionAdapter : RegionAdapterBase&lt;Ribbon&gt; { private Ribbon _ribbonTarget; public RibbonRegionAdapter(IRegionBehaviorFactory regionBehaviorFactory) : base(regionBehaviorFactory) { } protected override void Adapt(IRegion region, Ribbon regionTarget) { _ribbonTarget = regionTarget; region.Views.CollectionChanged += delegate { foreach (RibbonTab tab in region.Views.Cast&lt;RibbonTab&gt;()) { if (!_ribbonTarget.Items.Contains(tab)) { _ribbonTarget.Items.Add(tab); } } }; } protected override IRegion CreateRegion() { return new SingleActiveRegion(); } } </code></pre> <p>BootStrapper.cs - To register our regionAdapter</p> <pre><code> protected override RegionAdapterMappings ConfigureRegionAdapterMappings() { RegionAdapterMappings mappings = base.ConfigureRegionAdapterMappings(); if (mappings != null) { mappings.RegisterMapping(typeof(Ribbon), this.Container.Resolve&lt;RibbonRegionAdapter&gt;()); } return mappings; } </code></pre> <p>CarRibbonTab.xaml</p> <pre><code>&lt;ribbon:RibbonTab x:Class="CarManager.Modules.CarModule.Views.CarRibbonTab" xmlns:ribbon="clr-namespace:Microsoft.Windows.Controls.Ribbon;assembly=RibbonControlsLibrary" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" mc:Ignorable="d" Header="Officers"&gt; &lt;ribbon:RibbonGroup Header="New"&gt; &lt;/ribbon:RibbonGroup&gt; &lt;ribbon:RibbonGroup Header="Manage"&gt; &lt;ribbon:RibbonButton Label="Make" LargeImageSource="..\Resources\make.png" /&gt; &lt;ribbon:RibbonButton Label="Inventory" LargeImageSource="..\Resources\Inventory.png" /&gt; &lt;ribbon:RibbonButton Label="Assignments" /&gt; &lt;/ribbon:RibbonGroup&gt; &lt;/ribbon:RibbonTab&gt; </code></pre> <p>CarRibbonTab.cs - Code behind for the View</p> <pre><code>public partial class CarRibbonTab: RibbonTab { public CarRibbonTab() { InitializeComponent(); } } </code></pre> <p>Shell.xaml - Just showing the ribbon control</p> <pre><code>&lt;ribbon:Ribbon DockPanel.Dock="Top" Title="CarManager" prism:RegionManager.RegionName="RibbonRegion"&gt; &lt;ribbon:Ribbon.ApplicationMenu&gt; &lt;ribbon:RibbonApplicationMenu SmallImageSource="Images\Icon.png"&gt; &lt;ribbon:RibbonApplicationMenuItem Header="Exit" ImageSource="Images\ExitIcon.png"/&gt; &lt;/ribbon:RibbonApplicationMenu&gt; &lt;/ribbon:Ribbon.ApplicationMenu&gt; &lt;/ribbon:Ribbon&gt; </code></pre> <p>CarModule.cs - registering the view with the region </p> <pre><code> public class CarModule: IModule { private readonly IRegionManager _regionManager; private readonly IUnityContainer _container; public MenuItemViewModel MenuItem; public CarModule(IUnityContainer container, IRegionManager regionManager) { _container = container; _regionManager = regionManager; } public void Initialize() { //Ribbon _container.RegisterType&lt;Object, CarRibbonTab&gt;("CarRibbonTab"); _regionManager.AddToRegion("RibbonRegion", _container.Resolve&lt;CarRibbonTab&gt;()); } } </code></pre>

429

<p>I am working on a project where I have to calculate the totals of a transaction. Unfortunately, coupons have proven to be quite an issue. There are four types of coupons: transaction percentage, transaction dollar amounts, item percentage and item dollar amounts.</p> <p>I ended-up with this beast of a method, and was wondering if it is clear why I'm doing each part in the way I am. Are my comments are detailed enough? Is my code is more-or-less readable? Is there a way to simplify any of it?</p> <pre><code>private static Totals CalculateTotals(List&lt;Item&gt; items, List&lt;Coupon&gt; coupons, List&lt;Payment&gt; payments) { // Local vars, totals gets returned. Totals totals = new Totals(); decimal subtotal = 0; decimal workingSubtotal = 0; decimal discounts = 0; decimal tax = 0; decimal paid = 0; decimal taxRate = (Initialization.Location.TaxRate ?? 0); // Get the subtotal before any discounts. items.ForEach(i =&gt; subtotal += (i.Price ?? 0)); // An ItemCoupon takes a whole amount or percentage off of a single Item. // It can take it off of the most expensive, or least. Nothing in the middle. foreach (var coupon in coupons.OfType&lt;ItemCoupon&gt;()) { // new Item to hold the item to be discounted. Item item; // Find which item to discount. if (coupon.DiscountMostExpensive) { item = items.OrderByDescending(i =&gt; i.Price).FirstOrDefault(); } else // Otherwise, Discount LEAST Expensive. { item = items.OrderByDescending(i =&gt; i.Price).LastOrDefault(); } // Remove it from the list, before editing the price. items.Remove(item); // Set new price of item based on the type of coupon. (Percent, or whole dollar.) if (coupon.PercentageCoupon) { item.Price = Utils.CalculatePercentage(item.Price, coupon.DiscountPercentage); } else { item.Price = (item.Price ?? 0) - (coupon.DiscountAmount ?? 0); } // Add the item back to the list, with the new price. items.Add(item); } // Now that the single items have been discounted, let's get a wroking subtotal. items.ForEach(i =&gt; workingSubtotal += (i.Price ?? 0)); // A TransactionCoupon takes a whole amount or percentage off of the entire transaction. // To simplfy tax caculation--and because some items are non-taxable, // oh and, because we don't want any one item going below zero--we // split the discount over all the items, evenly. foreach (var coupon in coupons.OfType&lt;TransactionCoupon&gt;()) { if (coupon.PercentageCoupon) { // If it is a Percentage Coupon, simply take said percentage of off each item. items.ForEach(i =&gt; i.Price = Utils.CalculatePercentage(i.Price, coupon.DiscountPercentage)); } else { // If it is a whole amount, get each items percent of the of the subtotal, and discount them equally. // This would look way too confusing using lambda. foreach (var item in items) { decimal discount = (item.Price ?? 0) * ((coupon.DiscountAmount ?? 0) / workingSubtotal); item.Price = item.Price - discount; } } } // Let's get the new-new-new subtotal. workingSubtotal = 0; items.ForEach(i =&gt; workingSubtotal += (i.Price ?? 0)); // Calculate the total discounts. discounts += (subtotal - workingSubtotal); // Set tax for order. (This must be done after ALL discounts have been applied) foreach (var item in items.Where(i =&gt; i.Taxable)) { tax += ((item.Price ?? 0) * taxRate); } // Get the total amount paid. payments.ForEach(p =&gt; paid += p.Amount); // Add all the results to the Totals struct. totals.Subtotal = subtotal; // Never return the workingSubtotal; totals.Discounts = discounts; totals.Tax = tax; totals.Paid = paid; totals.Total = ((workingSubtotal + tax) - paid); return totals; } </code></pre>

438

<p>I'm working on a simple star rating system, and before I move on to actually "tallying" the votes, which I figure I'll just do with <code>$.ajax</code>, I wanted to make sure what I've done so far has been done as well as it can be.</p> <p><strong>JavaScript</strong></p> <pre><code>//max number of stars var max_stars = 5; //add images to the ratings div function fill_ratings() { var $rating = $("#rating"); if($rating.length) { for(i = 1; i &lt;= max_stars; i++) { $rating.append('&lt;img id="' + i + '"src="star_default.png" /&gt;'); } } } //variables... var hovered = 0; var has_clicked = false; var star_clicked = 0; function handle_ratings() { if(has_clicked == true) { for(i = 1; i &lt;= star_clicked; i++) { $('#rating img#' + i).attr('src', 'star.png'); } } $('#rating img').hover(function() { hovered = Number($(this).attr('id')); for(i = 1; i &lt;= max_stars; i++) { if(i &lt;= hovered) { $('#rating img#' + i).attr('src', 'star.png'); } else { $('#rating img#' + i).attr('src', 'star_default.png'); } } }).click(function() { //if they click a star, only set the stars to grey that are after it. star_clicked = Number($(this).attr('id')); has_clicked = true; for(i = 1; i &lt;= star_clicked; i++) { $('#rating img#' + i).attr('src', 'star.png'); //handle the vote here. eventually. } }).mouseout(function() { //if they haven't clicked a star, set all stars to grey. if(has_clicked !== true) { $('#rating img').attr('src', 'star_default.png'); } else { //show their rating for(i = 1; i &lt;= max_stars; i++) { if(i &lt;= star_clicked) { $('#rating img#' + i).attr('src', 'star.png'); } else { $('#rating img#' + i).attr('src', 'star_default.png'); } } } }); } $(function() { fill_ratings(); handle_ratings(); }); </code></pre> <p><strong>HTML</strong></p> <pre><code>&lt;div id="ratings"&gt;&lt;/div&gt; </code></pre> <p>The code works, but I was wondering if anyone notices any code that I can improve. Also, is there anything wrong with the way it...looks? Should I be commenting more, indenting differently, or any other "formatting" type things?</p>

444

<p>Can I make my template syntax simpler? I'm hoping to eliminate the <code>if</code> and maybe also the <code>for</code> block. </p> <p>This worked in the shell but I can't figure out the template syntax.</p> <pre><code>recipes[0].recipephotos_set.get(type=3).url </code></pre> <p>model.py</p> <pre><code>class Recipe(models.Model): .... class RecipePhotos(models.Model): PHOTO_TYPES = ( ('3', 'Sub Featured Photo: 278x209'), ('2', 'Featured Photo: 605x317'), ('1', 'Recipe Photo 500x358'), ) recipe = models.ForeignKey(Recipe) url = models.URLField(max_length=128,verify_exists=True) type = models.CharField("Type", max_length=1, choices=PHOTO_TYPES) </code></pre> <p>view.py</p> <pre><code>recipes = Recipe.objects.filter(recipephotos__type=3) </code></pre> <p>template.html</p> <pre><code>{% for recipe in recipes %} {% for i in recipe.recipephotos_set.all %} {% if i.type == '3' %} {{ i.url }} {% endif %} {% endfor %} &lt;a href="/recipe/{{ recipe.recipe_slug }}/"&gt;{{ recipe.recipe_name }}&lt;/a&gt;&lt;/li&gt; {% empty %} </code></pre>

445

<p>I have the following method:</p> <pre><code>private void removeUnnecessaryLines(List&lt;ScatterViewItem&gt; list) { List&lt;Line&gt; remove = new List&lt;Line&gt;(); foreach (Line line in lines) { SourceFile destination = (line.Tag as Call).getCallee(); foreach (ScatterViewItem svi in list) { SourceFile test = svi.Tag as SourceFile; if (test.Equals(destination)) { remove.Add(line); } } } foreach (Line l in remove) { lines.Remove(l); Dependencies.Children.Remove(l); } } </code></pre> <p>As you can see, there is a lot of iteration and casting. Is there a simple way to improve that?</p>

462

<p>I have a very simple PHP MVC library for my auto-didactic pedagogical purposes. I'm having a little trouble figuring out how to add in the observer patterns as show in <a href="http://en.wikipedia.org/wiki/File:ModelViewControllerDiagram2.svg" rel="nofollow noreferrer">this UML diagram from Wikipedia</a>.</p> <p><code>model</code> is simply contains an array and acts as a key-value store. <code>contrlr</code> accepts input, ostensibly from <code>$_POST</code>, to update a model.</p> <p>So then the observation relationships between the three are where my understanding breaks down. I have <code>contrlr</code> implementing <code>SplOberserver</code> and <code>SplSubject</code>, but how exactly should I handle communication between them? Concatenate strings to <code>strHtml</code>?</p> <p>Please note that I want to have these classes conform to the UML diagram linked from Wikipedia above.</p> <pre><code>class model { private $arrValues = array(); public function __get($var) { return $this-&gt;arrValues[$var]; } public function __set($var, $val) { $this-&gt;arrValues[$var] = $val; } } class contrlr implements SplOberver, SplSubject { private $objModel; public function __construct( model $objModel ) { $this-&gt;objModel = $objModel; } public function parsePost( array $arrPost ) { foreach ( $arrPost as $key =&gt; $value ) { $this-&gt;objModel-&gt;$key = $value; } } public function update() { } public function attach() { } public function detach() { } } class view implements SplObserver { private $strHtml; public function getHtml() { return $this-&gt;strHtml; } } </code></pre>

465

<p>I'm new into Javascript, and I'm not sure that is a good approach. The code works, and does what I need it to do but I'm sure I didn't do the things the right way.</p> <p>Can you give me feedback about the implementation idea and code?</p> <p>So, let's say that in index.html I have the following code into body section.</p> <pre><code>&lt;script type="text/javascript" src="js/main.js" language="javascript"&gt;&lt;/script&gt; </code></pre> <p>The content of the main.js file is the following:</p> <pre><code>document.write('&lt;script language="javascript" type="text/javascript" &gt;'); function loaded() { } loaded(); document.write('&lt;/script&gt;'); </code></pre> <p>I know that using document.write it is not a smart thing at all. I'm sure that other things are faulty, but I'm newbie and I'm looking for your feedback.</p>

466