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How can I force Powershell to return an array when a call only returns one object?
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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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Creating the Singleton design pattern in PHP5
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/**
* Singleton class
*
*/
final class UserFactory
{
/**
* Call this method to get singleton
*
* @return UserFactory
*/
public static function Instance()
{
static $inst = null;
if ($inst === null) {
$inst = new UserFactory();
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What does “program to interfaces, not implementations” mean?
...t worried about implementation and the interface signature determines what all operations can be done. This can be used to change the behavior of a program at run-time. It also helps you to write far better programs from the maintenance point of view.
Here's a basic example for you.
public enum La...
What is the meaning of single and double underscore before an object name?
...at least two leading underscores, at most one trailing underscore) is textually replaced with _classname__spam, where classname is the current class name with leading underscore(s) stripped. This mangling is done without regard to the syntactic position of the identifier, so it can be used to define...
When to use enumerateObjectsUsingBlock vs. for
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Ultimately, use whichever pattern you want to use and comes more naturally in the context.
While for(... in ...) is quite convenient and syntactically brief, enumerateObjectsUsingBlock: has a number of features that may or may not prove interesting:
enumerateObjectsUsingBlock: will be as fas...
How to make a valid Windows filename from an arbitrary string?
...: Bar" that I want to use as a filename, but on Windows the ":" char isn't allowed in a filename.
14 Answers
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How to sort an IEnumerable
How can I sort an IEnumerable<string> alphabetically. Is this possible?
4 Answers
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How can I quickly sum all numbers in a file?
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For a Perl one-liner, it's basically the same thing as the awk solution in Ayman Hourieh's answer:
% perl -nle '$sum += $_ } END { print $sum'
If you're curious what Perl one-liners do, you can deparse them:
% perl -MO=Deparse -nle '$sum += $_ } END ...
What algorithm does Readability use for extracting text from URLs?
... the "relevant" text from a URL by eliminating the text related to ads and all the other clutter.After several months of researching, I gave it up as a problem that cannot be accurately determined. (I've tried different ways but none were reliable)
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CSS hack大全 - 创意 - 清泛网 - 专注C/C++及内核技术
...io:0){.bb{background-color:#f1ee18}}{} /* Safari(Chrome) 有效 */
@media all and (min-width: 0px){ .bb{background-color:#f1ee18;/*opera and Safari(Chrome) and firefox*/ background-color:#4cac70\0;}/* 仅 Opera 有效 */ }{}
.bb, x:-moz-any-link, x:default{background-color:#4eff00;/*IE7、Firef...