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Why does += behave unexpectedly on lists?
...
The general answer is that += tries to call the __iadd__ special method, and if that isn't available it tries to use __add__ instead. So the issue is with the difference between these special methods.
The __iadd__ special method is for an in-place addition, that i...
Is there a generator version of `string.split()` in Python?
...plitlines chops off the trainling newline though (something that I don't really like...); if you wanted to replicated that part of the behavior, you could use grouping: (m.group(2) or m.group(3) for m in re.finditer('((.*)\n|(.+)$)', s)). PS: I guess the outer paren in the RE are not needed; I just ...
C# Sortable collection which allows duplicate keys
... Use this Comparer e.g. with SortedLists or SortedDictionaries, that don't allow duplicate keys
/// </summary>
/// <typeparam name="TKey"></typeparam>
public class DuplicateKeyComparer<TKey>
:
IComparer<TKey> where TKey : IComparable
{
#...
How does JavaScript .prototype work?
...ing languages but I've written my fair share of JavaScript code. I never really got my head around this prototype-based programming, does any one know how this works?
...
Django rest framework nested self-referential objects
... the `subcategories` field
return CategorySerializer()
Actually, as you've noted the above isn't quite right.
This is a bit of a hack, but you might try adding the field in after the serializer is already declared.
class CategorySerializer(serializers.ModelSerializer):
parentCat...
How can I multiply and divide using only bit shifting and adding?
...kes a constant multiple of time compared to addition and shifting. If I recall correctly, modern processors, if pipelined properly, can do multiplication just about as fast as addition, by messing with the utilization of the ALUs (arithmetic units) in the processor.
...
When do we need curly braces around shell variables?
...xpand the variable identified by foobar.
Curly braces are also unconditionally required when:
expanding array elements, as in ${array[42]}
using parameter expansion operations, as in ${filename%.*} (remove extension)
expanding positional parameters beyond 9: "$8 $9 ${10} ${11}"
Doing this every...
Adding external library into Qt Creator project
... this is like this:
LIBS += -L/path/to -lpsapi
This way it will work on all platforms supported by Qt. The idea is that you have to separate the directory from the library name (without the extension and without any 'lib' prefix). Of course, if you are including a Windows specific lib, this reall...
What is the difference between require_relative and require in Ruby?
... the docs:
require_relative complements the builtin method require by allowing you to load a file that is relative to the file containing the require_relative statement.
For example, if you have unit test classes in the "test" directory, and data for them under the test "test/data" directo...
Why is TypedReference behind the scenes? It's so fast and safe… almost magical!
...ecification, the constructs used to implement them under the hood (vararg calling convention, TypedReference type, arglist, refanytype, mkanyref, and refanyval instructions) are perfectly documented in the CLI Specification (ECMA-335) in the Vararg library.
Being defined in the Vararg Library makes ...