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How do I check if a variable exists?
...have nested functions, variables in outer scopes. If you want to check for all of them, you're probably best off triggering NameError after all.
– Petr Viktorin
Jun 10 '14 at 20:18
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Difference between -pthread and -lpthread while compiling
...that get defined when the -pthread option gets used on the GCC package installed on my Ubuntu machine:
$ gcc -pthread -E -dM test.c > dm.pthread.txt
$ gcc -E -dM test.c > dm.nopthread.txt
$ diff dm.pthread.txt dm.nopthread.txt
152d151
< #define _REENTRANT 1
208d206
< #define _...
Writing handler for UIAlertAction
...ActionStyle.Destructive,handler: { action in
print("pressed")
}))
All the answers above are correct i am just showing another way that can be done.
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How do I create a link using javascript?
....attr('href',desiredLink);
a.text(desiredText);
$('body').append(a);
In all the above examples you can append the anchor to any element, not just to the 'body', and desiredLink is a variable that holds the address that your anchor element points to, and desiredText is a variable that holds the te...
Check if a variable is a string in JavaScript
...ing both typeof and instanceof feels like good advice if your code may be called by others'. @MarkAmery's postmessage edge case matters if you're asking "what was I just postmessaged?" - but you'd expect that to be handled at the interface and not allowed to propagate. Elsewhere, it seems correct t...
Multiprocessing: How to use Pool.map on a function defined in a class?
...
[p.join() for p in proc]
return [p.recv() for (p, c) in pipe]
if __name__ == '__main__':
print parmap(lambda x: x**x, range(1, 5))
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Check if something is (not) in a list in Python
... @nightcracker That makes no sense as A not in B is reduced to doing not B.__contains__(A) which is the same as what not A in B is reduced to which is not B.__contains__(A).
– Dan D.
May 2 '12 at 0:33
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Difference between Ctrl+Shift+F and Ctrl+I in Eclipse
... just format tabs/whitespaces in code and pressing CTRL + SHIFT + F format all code that is format tabs/whitespaces and also divide code lines in a way that it is visible without horizontal scroll.
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The conversion of a datetime2 data type to a datetime data type resulted in an out-of-range value
...orm (headline, story, and image). ApplyPropertyChanges applies changes to all properties of the object, including your uninitialized DateTime, which is set to 0001-01-01, which is outside of the range of SQL Server's DATETIME.
Rather than using ApplyPropertyChanges, I'd suggest retrieving the obje...
Passing Data between View Controllers
...h it onto nav stack.
ViewControllerB *viewControllerB = [[ViewControllerB alloc] initWithNib:@"ViewControllerB" bundle:nil];
viewControllerB.isSomethingEnabled = YES;
[self pushViewController:viewControllerB animated:YES];
This will set isSomethingEnabled in ViewControllerB to BOOL value YES.
P...