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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 can I perform a str_replace in JavaScript, replacing text in JavaScript?
...erf, you can have different levels of efficiency for creating a regex, but all of them are significantly slower than a simple string replace. The regex is slower because:
Fixed-string matches don't have backtracking, compilation steps, ranges, character classes, or a host of other features that ...
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...
The tilde operator in Python
...a unary operator (taking a single argument) that is borrowed from C, where all data types are just different ways of interpreting bytes. It is the "invert" or "complement" operation, in which all the bits of the input data are reversed.
In Python, for integers, the bits of the twos-complement repr...
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...
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...
How to automatically start a service when running a docker container?
... @KarlMorrison docker exec -it <CONTAINER NAME> mysql /etc/init.d/mysqld restart
– kaiser
Mar 14 '16 at 0:46
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Getting root permissions on a file inside of vi? [closed]
...eed to add your user to sudoer file first, enter the root user, and open /etc/sudoers file, add your_username ALL=(ALL) ALL under the line root ALL=(ALL) ALL, quit and save.
– coolesting
Oct 25 '11 at 3:18
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How to change the color of an svg element?
...gt;
And in CSS use the no-svg class from Modernizr (CDN: http://ajax.aspnetcdn.com/ajax/modernizr/modernizr-2.7.2.js ) to check for SVG support. If there is no SVG support the SVG block will be ignored and the image will be displayed, otherwise the image will be removed from the DOM tree (display:...
PATH issue with pytest 'ImportError: No module named YadaYadaYada'
I used easy_install to install pytest on a mac and started writing tests for a project with a file structure likes so:
20 A...