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What is getattr() exactly and how do I use it?
... understand about getattr() is that getattr(li, "pop") is the same as calling li.pop .
14 Answers
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What would a “frozen dict” be?
...).
The most common reason to want such a type is when memoizing function calls for functions with unknown arguments. The most common solution to store a hashable equivalent of a dict (where the values are hashable) is something like tuple(sorted(kwargs.iteritems())).
This depends on the sorting n...
C++ compiling on Windows and Linux: ifdef switch [duplicate]
... @MestreLion The Predef project has since been absorbed into Boost, but all the macros are still listed in the documentation here: boost.org/doc/libs/release/libs/predef/doc/html/index.html
– rubenvb
Mar 26 '16 at 12:43
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Elasticsearch query to return all records
I have a small database in Elasticsearch and for testing purposes would like to pull all records back. I am attempting to use a URL of the form...
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How to get a complete list of object's methods and attributes?
...butes, the short answer is: no. The problem is that the attributes are actually defined as the arguments accepted by the getattr built-in function. As the user can reimplement __getattr__, suddenly allowing any kind of attribute, there is no possible generic way to generate that list. The dir functi...
C++ mark as deprecated
...erface that I want to deprecate with portable C++.
When I Googled for this all I got was a Microsoft specific solution; #pragma deprecated and __declspec(deprecated) .
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Objective-C ARC: strong vs retain and weak vs assign
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@Pascal: weak references aren't allowed in deployment targets where the os is not 5.0 or higher. So for older projects you can still use assign, but if you move to newer versions you have to switch to weak
– Mattia
Feb...
How do I create a constant in Python?
.... This is the closest equivalent to Java's final. However, it does not actually prevent reassignment:
from typing import Final
a: Final = 1
# Executes fine, but mypy will report an error if you run mypy on this:
a = 2
sha...
Windows threading: _beginthread vs _beginthreadex vs CreateThread C++
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CreateThread() is a raw Win32 API call for creating another thread of control at the kernel level.
_beginthread() & _beginthreadex() are C runtime library calls that call CreateThread() behind the scenes. Once CreateThread() has returned, _beginthread/ex...
Is arr.__len__() the preferred way to get the length of an array in Python?
...ples:
my_tuple = (1,2,3,4,5)
len(my_tuple)
# 5
And strings, which are really just arrays of characters:
my_string = 'hello world'
len(my_string)
# 11
It was intentionally done this way so that lists, tuples and other container types or iterables didn't all need to explicitly implement a public...