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Why use Abstract Base Classes in Python?
...emented classes.
Long version
There is a contract between a class and its callers. The class promises to do certain things and have certain properties.
There are different levels to the contract.
At a very low level, the contract might include the name of a method or its number of parameters.
In a s...
Should __init__() call the parent class's __init__()?
...
In Python, calling the super-class' __init__ is optional. If you call it, it is then also optional whether to use the super identifier, or whether to explicitly name the super class:
object.__init__(self)
In case of object, calling th...
SASS - use variables across multiple files
I would like to keep one central .scss file that stores all SASS variable definitions for a project.
6 Answers
...
Django filter queryset __in for *every* item in list
...
Summary:
One option is, as suggested by jpic and sgallen in the comments, to add .filter() for each category. Each additional filter adds more joins, which should not be a problem for small set of categories.
There is the aggregation approach. This query would be shorter and...
“Notice: Undefined variable”, “Notice: Undefined index”, and “Notice: Undefined offset” using PHP
... can be used to detect if a variable has been already initialized. Additionally and more ideal is the solution of empty() since it does not generate a warning or error message if the variable is not initialized.
From PHP documentation:
No warning is generated if the variable does not exist. T...
__FILE__ macro shows full path
....com/pipermail/cmake/2013-January/053117.html
I'm copying the tip so it's all on this page:
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -D__FILENAME__='\"$(subst
${CMAKE_SOURCE_DIR}/,,$(abspath $<))\"'")
If you're using GNU make, I see no reason you couldn't extend this to your own makefiles. ...
Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4
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If during the evaluation of an expression, the result is not mathematically defined or not in the range of
representable values for its type, the behavior is undefined. [ Note: most existing implementations of C++
ignore integer overflows. Treatment of division by zero, forming a remainde...
How can I swap positions of two open files (in splits) in vim?
... 'hide buf' markedBuf
endfunction
nmap <silent> <leader>mw :call MarkWindowSwap()<CR>
nmap <silent> <leader>pw :call DoWindowSwap()<CR>
To use (assuming your mapleader is set to \) you would:
Move to the window to mark for the swap via
ctrl-w movement
Type ...
How to install Boost on Ubuntu
I'm on Ubuntu, and I want to install Boost. I tried with
7 Answers
7
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A python class that acts like dict
...er) instead of simply delegating to the instance's __dict__ - which essentially means you're creating two dicts for every instance.
– Aaron Hall♦
Jan 8 '17 at 0:39
8
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