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Determine if map contains a value for a key?
...
Obviously you can write your own getValue() routine if you want (also in C++, there is no reason to use out), but I would suspect that once you get the hang of using std::map::find() you won't want to waste your time.
Also your code is slightly wrong:
m.find('2'); will search the map for a keyva...
Is there a difference between “==” and “is”?
...e value, but are distinct entities. But what about this?
>>> c = 200
>>> d = 200
>>> c == d
True
>>> c is d
True
This is inconsistent with the earlier result. What's going on here? It turns out the reference implementation of Python caches integer objects in th...
How to avoid “if” chains?
...ltogether.
Option 1. You can't do this: use finally
Unfortunately, as a c++ developer, you can't do this. But this is the number one answer for languages that contain a finally keyword, since this is exactly what it is for.
try
{
if (!ok)
{
_log.Error("oops");
return;
...
Is there a SASS.js? Something like LESS.js?
... hasn't been updated in 2 years, I might interest you in sass.js. It's the C++ library libsass (also used by node-sass) compiled to JavaScript using Emscripten. An implementation to compile scss stylesheets linked or inlined in html can be found at sass.link.js.
Try out sass.js using the interactiv...
Python - Create a list with initial capacity
...3587.204933ms
doAllocate: 2701.154947ms
doGenerator: 1721.098185ms
While C++ gives (built with MSVC, 64-bit, Optimizations enabled)
Elements: 100000, Iterations: 144
doAppend: 74.0042ms
doReserve: 27.0015ms
doAllocate: 5.0003ms
C++ debug build produces:
Elements: 100000, Iterations: 144
doAppe...
Is there a difference between copy initialization and direct initialization?
...
C++17 Update
In C++17, the meaning of A_factory_func() changed from creating a temporary object (C++<=14) to just specifying the initialization of whatever object this expression is initialized to (loosely speaking) in C+...
Rolling median algorithm in C
...rc/Trunmed.c a few times as I wanted something similar too in a standalone C++ class / C subroutine. Note that this are actually two implementations in one, see src/library/stats/man/runmed.Rd (the source of the help file) which says
\details{
Apart from the end values, the result \code{y = runme...
How to initialize const member variable in a class?
...d into many translation units. However, to avoid complicated linker rules, C++ requires that every object has a unique definition. That rule would be broken if C++ allowed in-class definition of entities that needed to be stored in memory as objects.
A const variable has to be declared within the ...
Why cast unused return values to void?
...o ensure that where necessary error codes are always handled.
I think for C++ this is probably the only place that I prefer to use C-style casts too, since using the full static cast notation just feels like overkill here. Finally, if you're reviewing a coding standard or writing one, then it's al...
What's the best way to parse a JSON response from the requests library?
.../get') >>> r.json <bound method Response.json of <Response [200]>> >>> r.json() {'args': {}, ...}
– pswaminathan
Oct 29 '18 at 14:47
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