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What does ||= (or-equals) mean in Ruby?
...ling-list that discuss this issue.
Here's one: The definitive list of ||= (OR Equal) threads and pages
If you really want to know what is going on, take a look at Section 11.4.2.3 "Abbreviated assignments" of the Ruby Language Draft Specification.
As a first approximation,
a ||= b
is equivalent to
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NSString property: copy or retain?
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For attributes whose type is an immutable value class that conforms to the NSCopying protocol, you almost always should specify copy in your @property declaration. Specifying retain is something you almost never want in such ...
Is gcc's __attribute__((packed)) / #pragma pack unsafe?
In C, the compiler will lay out members of a struct in the order in which they're declared, with possible padding bytes inserted between members, or after the last member, to ensure that each member is aligned properly.
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Why do you need explicitly have the “self” argument in a Python method?
...cit rather than based on a rule.
Additionally, since nothing is implied or assumed, parts of the implementation are exposed. self.__class__, self.__dict__ and other "internal" structures are available in an obvious way.
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How to get a key in a JavaScript object by its value?
... associative array. Is there a simple function allowing me to get the key for a value, or do I have to iterate the object and find it out manually?
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Most useful NLog configurations [closed]
What are the best or most useful configurations for logging with NLog? (These can be simple or complex, as long as they're useful.)
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What is DOCTYPE?
...use the DOCTYPE to determine how to render a page. Not including a DOCTYPE or including an incorrect one can trigger quirks mode.
The kicker here is, that quirks mode in Internet Explorer is quite different from quirks mode in Firefox (and other browsers); meaning that you'll have a much harder job...
JavaScript check if variable exists (is defined/initialized)
Which method of checking if a variable has been initialized is better/correct?
(Assuming the variable could hold anything (string, int, object, function, etc.))
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Using StringWriter for XML Serialization
I'm currently searching for an easy way to serialize objects (in C# 3).
6 Answers
6
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RegEx for Javascript to allow only alphanumeric
... find a reg ex that only allows alphanumeric. So far, everyone I try only works if the string is alphanumeric, meaning contains both a letter and a number. I just want one what would allow either and not require both.
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