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Add list to set?
...a set because lists are mutable, meaning that you can change the contents of the list after adding it to the set.
You can however add tuples to the set, because you cannot change the contents of a tuple:
>>> a.add(('f', 'g'))
>>> print a
set(['a', 'c', 'b', 'e', 'd', ('f', 'g')])...
C++ auto keyword. Why is it magic?
From all the material I used to learn C++, auto has always been a weird storage duration specifier that didn't serve any purpose. But just recently, I encountered code that used it as a type name in and of itself. Out of curiosity I tried it, and it assumes the type of whatever I happen to assig...
How can I avoid running ActiveRecord callbacks?
I have some models that have after_save callbacks. Usually that's fine, but in some situations, like when creating development data, I want to save the models without having the callbacks run. Is there a simple way to do that? Something akin to...
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Node.js get file extension
... Try 'filename.css.gz'.split('.').slice(1).join('.') to get all extensions
– Trevor
Jul 31 '17 at 21:53
11
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Remove non-utf8 characters from string
...eplacement is whatever was captured into group 1. This effectively removes all invalid bytes.
It is possible to repair the string, by encoding the invalid bytes as UTF-8 characters. But if the errors are random, this could leave some strange symbols.
$regex = <<<'END'
/
(
(?: [\x00-...
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...
Apply function to all elements of collection through LINQ [duplicate]
...ently started off with LINQ and its amazing. I was wondering if LINQ would allow me to apply a function - any function - to all the elements of a collection, without using foreach. Something like python lambda functions.
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How can you profile a Python script?
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Python includes a profiler called cProfile. It not only gives the total running time, but also times each function separately, and tells you how many times each function was called, making it easy to determine where you should make optimizations.
You c...
Python String and Integer concatenation [duplicate]
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Backticks are all sorts of silly.
– habnabit
May 17 '10 at 8:58
3
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Is there a replacement for unistd.h for Windows (Visual C)?
...nsole program written for Unix to the Windows platform ( Visual C++ 8.0 ). All the source files include "unistd.h", which doesn't exist. Removing it, I get complaints about misssing prototypes for 'srandom', 'random', and 'getopt'.
I know I can replace the random functions, and I'm pretty sure I ca...