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What do (lambda) function closures capture?
...the name and scope of the variable, not the object it's pointing to. Since all the functions in your example are created in the same scope and use the same variable name, they always refer to the same variable.
EDIT: Regarding your other question of how to overcome this, there are two ways that com...
Referring to the null object in Python
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SyntaxError: cannot assign to keyword
It's therefore safe to assume that all None references are the same. There isn't any "custom" None.
To test for None use the is operator
When writing code you might be tempted to test for Noneness like this:
if value==None:
pass
Or to test for falsehood l...
How can I custom-format the Autocomplete plug-in results?
...ue, redefining an internal function in a library, I have come to learn is called monkey-patching. Here's how I did it:
function monkeyPatchAutocomplete() {
// don't really need this, but in case I did, I could store it and chain
var oldFn = $.ui.autocomplete.prototype._renderItem;
...
python exception message capturing
...work, I get syntax error, what is the proper way of doing this for logging all kind of exceptions to a file
11 Answers
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Disable a method in a ViewSet, django-rest-framework
...ethods but I did not able to find out how to disable the PATCH method specially if you are using routers.
– Muneeb Ahmad
Mar 31 '15 at 14:56
3
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When is “i += x” different from “i = i + x” in Python?
...
This depends entirely on the object i.
+= calls the __iadd__ method (if it exists -- falling back on __add__ if it doesn't exist) whereas + calls the __add__ method1 or the __radd__ method in a few cases2.
From an API perspective, __iadd__ is supposed to be used fo...
Redirect stdout to a file in Python?
...t it back when you're done, sys.stdout = stdout. That way if you're being called from a function that uses print you don't screw them up.
– mgold
Dec 20 '12 at 15:06
4
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How do I change the working directory in Python?
...If the exception is thrown, do not perform any recursive operations, especially destructive ones. They will operate on the old path and not the new one.
Return to your old directory when you're done. This can be done in an exception-safe manner by wrapping your chdir call in a context manager, lik...
Why do we need virtual functions in C++?
... a rat."
So far so good, right? Animals eat generic food, cats eat rats, all without virtual.
Let's change it a little now so that eat() is called via an intermediate function (a trivial function just for this example):
// This can go at the top of the main.cpp file
void func(Animal *xyz) { xyz-...
How to set environment variables in Python?
I need to set some environment variables in the Python script and I want all the other scripts that are called from Python to see the environment variables' set.
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