Move in C++ without a std:move
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Move in C++ without a std:move
1–10 of 75 posts
Re: Move in C++ without a std:move
#2I'd push back slightly on move — at small scale the opposite has been true for me.
Re: Move in C++ without a std:move
#3I'd push back slightly on move — at small scale the opposite has been true for me.
Not sure what you mean, but std::move is one of the greatest tools in C++
Re: Move in C++ without a std:move
#4If the author is reading: both complicated examples are the same.
Re: Move in C++ without a std:move
#5Unfortunately, I don't think there's getting away from just understanding value semantics to get the correct and/or performant behavior.
Re: Move in C++ without a std:move
#6If the author is reading: both complicated examples are the same.
Yeah, the second one is supposed to read `Apple&& Cat(Apple&& val) {
return val;
}` — but the return type's `&&` was omitted by accident.
Re: Move in C++ without a std:move
#7What is that makes NVRO so much more difficult to implement? Why couldn't they mandate that just like RVO?
Do compilers literally just special case a simple return statement of a direct construction or something?
Re: Move in C++ without a std:move
#8Re: Move in C++ without a std:move
#9Earlier quoted context omitted.
Not sure what you mean, but std::move is one of the greatest tools in C++
This is one case where Rust benefited from C++’s experience — move by default with opt-in clone/copy is IMO the better setup.
And the most important idea: destructive moves.
Since C++ doesn't track lifetimes it has to leave the object in a "valid state" after a move and the destructor still runs which has to have a check if it should do something or not.
Re: Move in C++ without a std:move
#10What is that makes NVRO so much more difficult to implement? Why couldn't they mandate that just like RVO? Do compilers literally just special case a simple return statement of a direct construction or something?
The simple cases are simple. However the complex cases get hard.
mytype foo() {
mytype one;
...
if(something) {
mytype two;
...
return two;
}
return one;
}