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How do I migrate a model out of one django app and into a new one?
...cy is set South will not guarantee that the common_cat table exists at the time when specific/0003_create_cat is run, throwing an django.db.utils.OperationalError: no such table: common_cat error at you.
South runs migrations in lexicographical order unless dependency is explicitly set. Since commo...
How to find list intersection?
...em slower than the pure list comp algorithms.
#!/usr/bin/env python
''' Time list- vs set-based list intersection
See http://stackoverflow.com/q/3697432/4014959
Written by PM 2Ring 2015.10.16
'''
from __future__ import print_function, division
from timeit import Timer
setup = 'from __ma...
@property retain, assign, copy, nonatomic in Objective-C
...age is no longer working. So, here is what I've learned in my (very) short time coding in Objective-C:
nonatomic vs. atomic
- "atomic" is the default. Always use "nonatomic". I don't know why, but the book I read said there is "rarely a reason" to use "atomic". (BTW: The book I read is the BNR "iOS...
Convert date to datetime in Python
Is there a built-in method for converting a date to a datetime in Python, for example getting the datetime for the midnight of the given date? The opposite conversion is easy: datetime has a .date() method.
...
Sort a list of tuples by 2nd item (integer value) [duplicate]
... I just wanted to say this is my most visited stackoverflow page of all time; i've been here like easily 500 times by now. Thank you cheeken, if only i could memorize this one line of code.
– will kinsman
Aug 19 at 3:08
...
In C#, what happens when you call an extension method on a null object?
... this argument is null:
default(string).MyExtension();
Works well at runtime, but produces the warning "Expression will always cause a System.NullReferenceException, because the default value of string is null".
share
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How do you run multiple programs in parallel from a bash script?
...re control over the running jobs and output. If two jobs print at the same time, GNU Parallel will make sure the output is not mixed.
– Ole Tange
Dec 25 '18 at 2:44
1
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Returning a C string from a function
..., especially 'down the road'.
In short, although my answer is correct - 9 times out of 10 you'll end up with a program that crashes if you use it that way, especially if you think it's 'good practice' to do it that way. In short: It's generally not.
For example, imagine some time in the future, th...
Why would one use the Publish/Subscribe pattern (in JS/jQuery)?
... me to the publish/subscribe pattern (in JS/jQuery), but I'm having a hard time getting to grips with why one would use this pattern over 'normal' JavaScript/jQuery.
...
Finding a substring within a list in Python [duplicate]
...ll lists, it doesn't make a difference, but consider this example:
import timeit
mylist = ['abc123'] + ['xyz123']*1000
sub = 'abc'
timeit.timeit('[s for s in mylist if sub in s]', setup='from __main__ import mylist, sub', number=100000)
# for me 7.949463844299316 with Python 2.7, 8.56884094499400...