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Creating the Singleton design pattern in PHP5

... /** * Singleton class * */ final class UserFactory { /** * Call this method to get singleton * * @return UserFactory */ public static function Instance() { static $inst = null; if ($inst === null) { $inst = new UserFactory(); ...
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How do I do base64 encoding on iOS?

... A really, really fast implementation which was ported (and modified/improved) from the PHP Core library into native Objective-C code is available in the QSStrings Class from the QSUtilities Library. I did a quick benchmark: a 5....
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How can I force Powershell to return an array when a call only returns one object?

... I actually feel like this is the most clear and safe option. You can reliably use ".Count - ge 1' on the collection or 'Foreach' – Jaigene Kang Jul 11 '17 at 22:24 ...
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What is the meaning of single and double underscore before an object name?

...at least two leading underscores, at most one trailing underscore) is textually replaced with _classname__spam, where classname is the current class name with leading underscore(s) stripped. This mangling is done without regard to the syntactic position of the identifier, so it can be used to define...
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How to find elements by class

...h to only find those divs with a given class using BS3: mydivs = soup.findAll("div", {"class": "stylelistrow"}) share | improve this answer | follow | ...
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Force CloudFront distribution/file update

... Good news. Amazon finally added an Invalidation Feature. See the API Reference. This is a sample request from the API Reference: POST /2010-08-01/distribution/[distribution ID]/invalidation HTTP/1.0 Host: cloudfront.amazonaws.com Authorization:...
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How to model type-safe enum types?

...ample above) does not offer exhaustive pattern matching. I have researched all the different enumeration patterns currently being used in Scala and give and overview of them in this StackOverflow answer (including a new pattern which offers the best of both scala.Enumeration and the "sealed trait +...
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What is the difference between C# and .NET?

.... The C# specification says only a very little about the environment (basically, that it should contain some types such as int, but that's more or less all). share | improve this answer | ...
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What does “program to interfaces, not implementations” mean?

...t worried about implementation and the interface signature determines what all operations can be done. This can be used to change the behavior of a program at run-time. It also helps you to write far better programs from the maintenance point of view. Here's a basic example for you. public enum La...
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When to use enumerateObjectsUsingBlock vs. for

... Ultimately, use whichever pattern you want to use and comes more naturally in the context. While for(... in ...) is quite convenient and syntactically brief, enumerateObjectsUsingBlock: has a number of features that may or may not prove interesting: enumerateObjectsUsingBlock: will be as fas...