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Standard alternative to GCC's ##__VA_ARGS__ trick?
There is a well-known problem with empty args for variadic macros in C99.
10 Answers
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How to create module-wide variables in Python? [duplicate]
...iables are local. You simply add a global declaration in your function, before you try to use the global.
def initDB(name):
global __DBNAME__ # add this line!
if __DBNAME__ is None: # see notes below; explicit test for None
__DBNAME__ = name
else:
raise RuntimeError("D...
Length of generator output [duplicate]
Python provides a nice method for getting length of an eager iterable, len(x) that is. But I couldn't find anything similar for lazy iterables represented by generator comprehensions and functions. Of course, it is not hard to write something like:
...
Execution of Python code with -m option or not
...n you use the -m command-line flag, Python will import a module or package for you, then run it as a script. When you don't use the -m flag, the file you named is run as just a script.
The distinction is important when you try to run a package. There is a big difference between:
python foo/bar/baz.p...
How to use Sphinx's autodoc to document a class's __init__(self) method?
Sphinx doesn't generate docs for __init__(self) by default. I have tried the following:
5 Answers
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How do I get Flask to run on port 80?
...hat error message because you have apache2 running on port 80.
If this is for development, I would just leave it as it is on port 5000.
If it's for production either:
Not Recommended
Stop apache2 first;
Not recommended as it states in the documentation:
You can use the builtin server dur...
Difference between __getattr__ vs __getattribute__
..._ is only invoked if the attribute wasn't found the usual ways. It's good for implementing a fallback for missing attributes, and is probably the one of two you want.
__getattribute__ is invoked before looking at the actual attributes on the object, and so can be tricky to implement correctly. Yo...
Performance difference for control structures 'for' and 'foreach' in C#
Which code snippet will give better performance? The below code segments were written in C#.
9 Answers
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How to watch for array changes?
...hod
Going the quick and dirty route, you could override the push() method for your array1:
Object.defineProperty(myArray, "push", {
enumerable: false, // hide from for...in
configurable: false, // prevent further meddling...
writable: false, // see above ^
value: function () {
for (var...
Inheritance and Overriding __init__ in python
...
should i look for a better book/tutorial?
– liewl
Apr 15 '09 at 20:54
2
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