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@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...
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
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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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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.
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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...
How can I use threading in Python?
...r() is better style for current Python. Super was relatively recent at the time that I provided this answer, hence calling directly to the super class rather than using super(). I'll update this to use super, though.
– Michael Aaron Safyan
Mar 6 '14 at 11:16
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Case insensitive 'in'
...ame in USERNAMES) would create only a generator and one needed string at a time - massive memory savings if you're doing this operation a lot. (even more savings, if you simply create a list of lowercase usernames that you reuse for checking every time)
– viraptor
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Angular JS: What is the need of the directive’s link function when we already had directive’s contro
...d in the controller since this is what is watching the template during run-time.
(4) Finally, controller is also used to be able to communicate among related directives. (Like myTabs example in https://docs.angularjs.org/guide/directive)
(5) It's true that we could've done all this in the link fun...
How to recursively find the latest modified file in a directory?
...ard for sort to keep everything in memory.
%T@ gives you the modification time like a unix timestamp, sort -n sorts numerically, tail -1 takes the last line (highest timestamp), cut -f2 -d" " cuts away the first field (the timestamp) from the output.
Edit: Just as -printf is probably GNU-only, ajr...