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Releasing memory in Python
...arena will not be released. In Python 3.3 the small object allocator was switched to using anonymous memory maps instead of the heap, so it should perform better at releasing memory.
Additionally, the built-in types maintain freelists of previously allocated objects that may or may not use the smal...
What's the fastest algorithm for sorting a linked list?
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It is reasonable to expect that you cannot do any better than O(N log N) in running time.
However, the interesting part is to investigate whether you can sort it in-place, stably, its worst-case behavior and so on.
Simon ...
How do I create a custom iOS view class and instantiate multiple copies of it (in IB)?
... instantiate an instance of your timer in IB simply drag out a UIView drop it on your view controller's view, and set it's class to your timer's class name.
Remember to #import your timer class in your view controller.
Edit: for IB design (for code instantiation see revision history)
I'm not ve...
CSS horizontal centering of a fixed div?
...t a div, which should be fixed on the screen, even if the page is scrolled it should always stay CENTERED in the middle of the screen!
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Git branch strategy for small dev team [closed]
We have a web app that we update and release almost daily. We use git as our VCS, and our current branching strategy is very simple and broken: we have a master branch and we check changes that we 'feel good about' into it. This works, but only until we check in a breaking change.
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Why do assignment statements return a value?
...ere are only a handful of expressions which are legal statements in C#: awaits of an expression, instance construction, increment, decrement, invocation and assignment expressions may be used where a statement is expected.
There is only one kind of expression in C# which does not produce some sort ...
Execute a terminal command from a Cocoa app
...andle *file = pipe.fileHandleForReading;
NSTask *task = [[NSTask alloc] init];
task.launchPath = @"/usr/bin/grep";
task.arguments = @[@"foo", @"bar.txt"];
task.standardOutput = pipe;
[task launch];
NSData *data = [file readDataToEndOfFile];
[file closeFile];
NSString *grepOutput = [[NSString all...
Using emit vs calling a signal as if it's a regular function in Qt
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emit is just syntactic sugar. If you look at the pre-processed output of function that emits a signal, you'll see emit is just gone.
The "magic" happens in the generated code for the signal emitting function, which you can loo...
How to UPSERT (MERGE, INSERT … ON DUPLICATE UPDATE) in PostgreSQL?
...ey) DO UPDATE (and ON CONFLICT (key) DO NOTHING), i.e. upsert.
Comparison with ON DUPLICATE KEY UPDATE.
Quick explanation.
For usage see the manual - specifically the conflict_action clause in the syntax diagram, and the explanatory text.
Unlike the solutions for 9.4 and older that are given below, ...
Split value from one field to two
...bername which contains both the last name and the first name of users. Is it possible to split those into 2 fields memberfirst , memberlast ?
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