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Is there a standard function to check for null, undefined, or blank variables in JavaScript?
...Javascript. Find it in the specification at the ToBoolean section.
Furthermore, if you do not know whether a variable exists (that means, if it was declared) you should check with the typeof operator. For instance
if( typeof foo !== 'undefined' ) {
// foo could get resolved and it's defined
}
...
How is Racket different from Scheme?
... [ ... ] as equivalent, R5RS does not, but R6RS does.
There are probably more, but on most other parts racket is a superset of Scheme.
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How to save username and password with Mercurial?
...e password in your system’s key ring instead of a plain text file, it is more secure. It is bundled with TortoiseHg on Windows, and there is currently a discussion about distributing it as a bundled extension on all platforms.
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Unique BooleanField value in Django?
... I tried editing to remove the need for try/except and to make the process more efficient but it was rejected.. Instead of get()ing the Character object and then save()ing it again, you just need to filter and update, which produces just one SQL query and helps keep the DB consistent: if self.is_the...
Is it possible to animate scrollTop with jQuery?
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How to create a memory leak in Java?
...l (small) objects, so small that even the ConcurrentLinkedQueue.Node takes more memory.
– bestsss
Jun 30 '11 at 19:49
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How to swap two variables in JavaScript
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std::wstring VS std::string
... using char are said "multibyte" (because each glyph is composed of one or more chars), while applications using wchar_t are said "widechar" (because each glyph is composed of one or two wchar_t. See MultiByteToWideChar and WideCharToMultiByte Win32 conversion API for more info.
Thus, if you work o...
How to send a message to a particular client with socket.io
...e socket object in a datastore? I'm assuming this doesn't work if you have more than one node process.
– chovy
Dec 9 '13 at 4:23
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Does use of final keyword in Java improve the performance?
...for inheritance or prohibit it" rule of thumb, I should probably use final more often for classes...
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