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Python hashable dicts

...n algol-like language (as apposed to the syntax free lisp dialects you normally find them in). Because of this, different passes through the input might see different grammars, so cached parse results are invalid, unless I also store the current version of the grammar along with the cached parse re...
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Python's equivalent of && (logical-and) in an if-statement

... different name in Python. The logical operators && and || are actually called and and or. Likewise the logical negation operator ! is called not. So you could just write: if len(a) % 2 == 0 and len(b) % 2 == 0: or even: if not (len(a) % 2 or len(b) % 2): Some additional information (...
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Javascript Functions and default parameters, not working in IE and Chrome

...or are you saying the Mozilla docs are inaccurate? – php-b-grader Jun 19 at 0:12  |  show 1 more comment ...
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How to avoid having class data shared among instances?

...problem you face is that x.list and y.list are the same list, so when you call append on one, it affects the other. – Matt Moriarity Nov 5 '09 at 14:04 ...
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Objective-C ARC: strong vs retain and weak vs assign

... @Pascal: weak references aren't allowed in deployment targets where the os is not 5.0 or higher. So for older projects you can still use assign, but if you move to newer versions you have to switch to weak – Mattia Feb...
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Code Golf: Collatz Conjecture

...sp+0x04], 2 jne .usage mov ebx, [esp+0x08] push dword [ebx+0x04] call atoi add esp, 4 cmp eax, 0 je .usage mov ebx, eax push eax push msg .loop: mov [esp+0x04], ebx call printf test ebx, 0x01 jz .even .odd: lea ebx, [1+ebx*2+ebx] jmp .loop .even: shr ebx, 1 ...
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Python time measure function

...e__, (time2-time1)*1000.0)) return ret return wrap Note I'm calling f.func_name to get the function name as a string(in Python 2), or f.__name__ in Python 3. share | improve this answ...
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How to implement an ordered, default dict? [duplicate]

...deredDict() and defaultdict() from collections in one object, which shall be an ordered, default dict . Is this possible? ...
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Is it possible to declare two variables of different types in a for loop?

...and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so: for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) { // ... } The above will give you: int i set to 1 double f set to 1.0 std::string s set to "...
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Fastest way to get the first object from a queryset in django?

...eturn None if there aren't any. There are lots of ways to do this which all work. But I'm wondering which is the most performant. ...