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Function in JavaScript that can be called only once
...
If by "won't be executed" you mean "will do nothing when called more than once", you can create a closure:
var something = (function() {
var executed = false;
return function() {
if (!executed) {
executed = true;
// do something
}
...
Python decorators in classes
... Test()
test.bar()
This avoids the call to self to access the decorator and leaves it hidden in the class namespace as a regular method.
>>> import stackoverflow
>>> test = stackoverflow.Test()
>>> test.bar()
start magic
normal call
end magic
>>>
edited t...
Python: How do I make a subclass from a superclass?
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The only reason to avoid super is if you don't understand the differences between how super works in Python, and how super/parent works in other languages. Admittedly this is not obvious to people coming from other languages, but I wouldn't conclude that that qualifies it as som...
Saving images in Python at a very high quality
...nd trying to get good figures in a latex document, save as an eps. Specifically, try something like this after running the commands to plot the image:
plt.savefig('destination_path.eps', format='eps')
I have found that eps files work best and the dpi parameter is what really makes them look good ...
How can I reference a commit in an issue comment on GitHub?
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To reference a commit, simply write its SHA-hash, and it'll automatically get turned into a link.
See also:
The Autolinked references and URLs / Commit SHAs section of
Writing on GitHub.
share
...
$_POST vs. $_SERVER['REQUEST_METHOD'] == 'POST'
...' (lower- or even mixed case). Does PHP automatically sanitize this on GET and POST?
– Boldewyn
Mar 22 '10 at 13:24
Af...
Are unused CSS images downloaded?
... "unused" and thusly, any images won't be downloaded.
Chrome 26 (possibly all of them, not sure), does download CSS images if they are applied to the <noscript> element, even when JS is enabled. (It isn't immediately clear to me why though, perhaps this is a bug?).
It does not download CSS i...
Check if Python Package is installed
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Name: numpy
Version: 1.11.1
Summary: NumPy: array processing for numbers, strings, records, and objects.
Home-page: http://www.numpy.org
Author: NumPy Developers
Author-email: numpy-discussion@scipy.org
License: BSD
Location: /home/***/anaconda2/lib/python2.7/site-packages
Requires:
Required-by: s...
How is the undo tree used in Vim?
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See also :h undo-redo, which lists all the commands and their usage.
There are two ways to traverse the undo tree. One is to go "back in time". g+ and g- will traverse all of the nodes in the tree in chronological or reverse-chronological order (which can...
How can I create an object and add attributes to it?
...ant to make a "bunch class", a very simple one already exists in Python -- all functions can have arbitrary attributes (including lambda functions). So, the following works:
obj = someobject
obj.a = lambda: None
setattr(obj.a, 'somefield', 'somevalue')
Whether the loss of clarity compared to the...