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What does [object Object] mean?
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Why does Object.prototype.toString.call(undefined) gives [object Undefined]?
– Suraj Jain
Jan 26 at 13:50
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Optimistic vs. Pessimistic locking
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Optimistic locking doesn't necessarily use a version number. Other strategies include using (a) a timestamp or (b) the entire state of the row itself. The latter strategy is ugly but avoids the need for a dedicated version column, in cases wher...
What does “O(1) access time” mean?
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To be pedantic, it doesn't mean that the runtime (or number of operations, etc.) is constant. It means that there is a constant such that the runtime (or number of operations, etc.) is bounded above by the constant. There could still be large v...
Determine whether an array contains a value [duplicate]
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What version of IE does this answer refer to?
– Vivian River
Feb 24 '12 at 22:20
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What's better at freeing memory with PHP: unset() or $var = null
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It was mentioned in the unset manual's page in 2009:
unset() does just what its name says - unset a variable. It does not force immediate memory freeing. PHP's garbage collector will do it when it see fits - by intention as soon, as those CPU cycles aren't needed anyway, or as late as ...
How to paste over without overwriting register
Does anyone know of a way to paste over a visually selected area without having the selection placed in the default register?
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How to 'grep' a continuous stream?
...e-buffered I get no output. However, after testing, it looks like GNU grep does what you describe. So like most things Unix, it depends on your platform's implementation. Since the question did not specify platform, your information appears to be false - after reviewing the code for BSD grep and com...
How can I trigger an onchange event manually? [duplicate]
...time textfield value via a calendar widget. Obviously, the calendar widget does something like this :
3 Answers
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What's the difference between libev and libevent?
... you also need to look elsewhere for an http library, because libev simply doesn't have one (for example, there is a very related library called libeio that does asynchronous I/O, which can be used independently or together with libev, so you can mix and match).
So in short, libev tries to do one t...
Rails: Why does find(id) raise an exception in rails? [duplicate]
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That still doesn't explain why it's the default behaviour where in most all other parts of ActiveRecord, the default behaviour is to return nil or false for failures, and leave the exception control flow to methods ending in a bang (#sa...