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What does new self(); mean in PHP?

... the parent class The first situation would look like this (I've removed all non-necessary code, for this example -- you'll have to add it back to get the singleton behavior)* : class MyParentClass { } class MyChildClass extends MyParentClass { public static function getInstance() { ...
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Handler is abstract ,cannot be instantiated

... @Glenn--, srsly, this just solved all manner of other errors in my code. ++ to this answer! – Joel Balmer Mar 12 '14 at 22:28 ...
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How can I uninstall an application using PowerShell?

... $app = Get-WmiObject -Class Win32_Product | Where-Object { $_.Name -match "Software Name" } $app.Uninstall() Edit: Rob found another way to do it with the Filter parameter: $app = Get-WmiObject -Class Win32_Product ` -Filter ...
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Rails check if yield :area is defined in content_for

... not really necessary to create a helper method: <% if @content_for_sidebar %> <div id="sidebar"> <%= yield :sidebar %> </div> <% end %> then of course in your view: <% content_for :sideb...
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Array versus List: When to use which?

...he underlying stream (and v.v.); quicker than BufferedStream etc; it internally uses an array-based model of objects (Foo[] rather than List<Foo>), since the size is fixed once built, and needs to be very fast. But this is definitely an exception; for general line-of-business processing, a L...
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Difference between dispatch_async and dispatch_sync on serial queue?

... I do mean serial execution. In point of view that all tasks are executed serial regards to other tasks in the same queue. Of cause it still can be concurrent regards to other queues. It is the whole point of GCD that tasks can be dispatched and executed concurrently. ...
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Do try/catch blocks hurt performance when exceptions are not thrown?

... { Console.WriteLine(ex.ToString()); } finally { d = Math.Sin(d); } } w.Stop(); Console.Write(" try/catch/finally: "); Console.WriteLine(w.ElapsedMilliseconds); w.Reset(); d = 0; w.Start(); for (int i = ...
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Detecting Unsaved Changes

...reunload methods as required. From the comments, the following references all input fields, without duplicating code: $(':input').change(function () { Using $(":input") refers to all input, textarea, select, and button elements. ...
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Are the decimal places in a CSS width respected?

...ractional pixels (in Chrome the values are truncated, so 50, 50.5 and 50.6 all show the same width). share | improve this answer | follow | ...
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Capturing mobile phone traffic on Wireshark

... suggestions: For Android phones, any network: Root your phone, then install tcpdump on it. This app is a tcpdump wrapper that will install tcpdump and enable you to start captures using a GUI. Tip: You will need to make sure you supply the right interface name for the capture and this varies from...