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How do I enumerate the properties of a JavaScript object? [duplicate]
...familiar with object-oriented programming would expect anything less! Typically, someone that brings this up has been subjected to Douglas Crockford's warnings about this, which still confuse me a bit. Again, inheritance is a normal part of OO languages and is therefore part of JavaScript, notwithst...
const vs constexpr on variables
...u can not modify them. However only PI2 is a compile-time constant. It shall be initialized at compile time. PI1 may be initialized at compile time or run time. Furthermore, only PI2 can be used in a context that requires a compile-time constant. For example:
constexpr double PI3 = PI1; // er...
How to concatenate two strings to build a complete path
...r -p $SUBFOLD2
And if you want to use readline so you get completion and all that, add a -e to the call to read:
read -e -p "Enter a directory: " BASEPATH
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Display help message with python argparse when script is called without any arguments
... what I needed. One question, can this be applied to subcommands too? I usually just get ``Namespace(output=None)`. How can I trigger an error easily on ALL subcommands? I'd like to trigger an error there.
– Jonathan Komar
May 20 '16 at 7:43
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How can I get PHPUnit MockObjects to return different values based on a parameter?
...ay('firstparam', 'secondparam', 'retval'),
array('modes', 'foo', array('Array', 'of', 'modes'))
)
)
);
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Check if a method exists
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You're looking for respondsToSelector:-
if ([foo respondsToSelector: @selector(bar)] {
[foo bar];
}
As Donal says the above tells you that foo can definitely handle receiving the bar selector. However, if foo's a proxy that forwards bar to some underlying object tha...
Why would I ever use push_back instead of emplace_back?
...ob is to generate the code you wrote. The optimizing compiler's job is actually to generate the code you would have written if you were an expert on platform-specific optimizations and did not care about maintainability, just performance.
The actual difference between these two statements is that t...
Hidden Features of MySQL
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Since you put up a bounty, I'll share my hard won secrets...
In general, all the SQLs I tuned today required using sub-queries. Having come from Oracle database world, things I took for granted weren’t working the same with MySQL. And my reading on MySQL tuning makes me conclude that MySQL is be...
How to check if a value exists in an array in Ruby
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Let me just note that internally, #include? still does perform looping. The coder is saved from writing the loop explicitly, though. I have added an answer that performs the task truly without looping.
– Boris Stitnicky
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Regular expression to match a word or its prefix
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Square brackets are meant for character class, and you're actually trying to match any one of: s, |, s (again), e, a, s (again), o and n.
Use parentheses instead for grouping:
(s|season)
or non-capturing group:
(?:s|season)
Note: Non-capture groups tell the engine that it doesn...