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Add custom messages in assert?
...rk; they’re compile-time constants and their use in this context is trivially optimized away. There is no runtime cost.
– zneak
Aug 9 '19 at 8:46
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CSS styling in Django forms
...ling, if you need an unique identifier its better to use id. Second its usually the template side's responsobilty to do exaclty this, Esspecially if you are going to access this class via frontend methods (js, css). I didn't say your answer is wrong. In my opinion its just bad practice (esspecially ...
Is errno thread-safe?
...t errno; so my question is, is it safe to check errno value after some calls or use perror() in multi-threaded code. Is this a thread safe variable? If not, then whats the alternative ?
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Circular (or cyclic) imports in Python
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There was a really good discussion on this over at comp.lang.python last year. It answers your question pretty thoroughly.
Imports are pretty straightforward really. Just remember the following:
'import' and 'from xxx import yyy' ...
What is the purpose of python's inner classes?
...dden from the outside world.
More readable, maintainable code: Nesting small classes within top-level classes places the code closer to where it is used.
The main advantage is organization. Anything that can be accomplished with inner classes can be accomplished without them.
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Unzip a file with php
...e it out by yourself. On the other hand, the fact that this code could actually be published online somewhere as the correct way to unzip a file is a bit frightening.
PHP has built-in extensions for dealing with compressed files. There should be no need to use system calls for this. ZipArchivedocs ...
How to track down a “double free or corruption” error
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If you're using glibc, you can set the MALLOC_CHECK_ environment variable to 2, this will cause glibc to use an error tolerant version of malloc, which will cause your program to abort at the point where the double free is done.
You can set this from gdb by using ...
Why use strict and warnings?
...tify how much it helps. It should suffice to say that they help unconditionally.
– ikegami
Nov 6 '11 at 19:42
1
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Difference between len() and .__len__()?
Is there any difference between calling len([1,2,3]) or [1,2,3].__len__() ?
4 Answers
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Best explanation for languages without null
... that every reference type gets this extra state in its space that is typically undesired. A string variable could be any sequence of characters, or it could be this crazy extra null value that doesn't map into my problem domain. A Triangle object has three Points, which themselves have X and Y va...