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Django queries - id vs pk
...ry key field i.e. you don't need to care whether the primary key field is called id or object_id or whatever.
It also provides more consistency if you have models with different primary key fields.
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Why does JQuery have dollar signs everywhere?
...ring your using noConflict (more below)
var divs = $("div"); // Find all divs
var divs = jQuery("div"); // Also find all divs, because
console.log($ === jQuery); // "true"
If you don't want to use the alias, you don't have to. And if you want $ to not be an alias for jQuery, you can use noC...
Why return NotImplemented instead of raising NotImplementedError
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It's because __lt__() and related comparison methods are quite commonly used indirectly in list sorts and such. Sometimes the algorithm will choose to try another way or pick a default winner. Raising an exception would break out of the s...
Why 0 is true but false is 1 in the shell?
The above will output 1 , which is contradictory with all other programming languages I know.
10 Answers
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How to make PDF file downloadable in HTML link?
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header("Content-Length: " . filesize($file));
flush(); // this doesn't really matter.
$fp = fopen($file, "r");
while (!feof($fp))
{
echo fread($fp, 65536);
flush(); // this is essential for large downloads
}
fclose($fp);
PS: and obviously run some sanity checks on the "file" variable t...
Multiprocessing: How to use Pool.map on a function defined in a class?
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[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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C dynamically growing array
...ynamic array implementations work by starting off with an array of some (small) default size, then whenever you run out of space when adding a new element, double the size of the array. As you can see in the example below, it's not very difficult at all: (I've omitted safety checks for brevity)
type...
How can I scale an image in a CSS sprite
...http://css-tricks.com/css-sprites/ , it talks about how can I crop off a smaller image from 1 bigger image. Can you please tell me if it is possible/how I can crop off a smaller image and then scale the cropped off region before I lay it out?
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Print PHP Call Stack
I'm looking for a way to print the call stack in PHP.
15 Answers
15
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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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