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Copy pathmove.cpp
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51 lines (33 loc) · 1.56 KB
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/*
# move constructor
# move semantics
Useful in situations where a class heap allocated data.
Made possible by C++11 rvalue references.
Basic idea: when copying from an rvalue, it is not necessary to make an expensive copy of it:
it suffices to acquire its data via swap, and leave it on a valid state (via a default constructor for example).
This is true because the rvalue passed to a copy constructor cannot be seen.
Value reference allows to overload the copy constructor based not on type,
but on the fact that a value is an rvalue or an lvalue!
No change must be done to the copy and swap idiom for move semantics to work for the assigment operator,
since in C++11 `int i = rvale` calls a move consttuctor on `i` while `int i = lvalue` calls a copy constructor.
# Sources
- http://stackoverflow.com/questions/3106110/what-is-move-semantics
- http://www.cprogramming.com/c++11/rvalue-references-and-move-semantics-in-c++11.html
- http://stackoverflow.com/questions/3413470/what-is-stdmove-and-when-should-it-be-used
# xvalue
# glvalue
# prvalue
In addition to the C99 rlvalues and values,
the C++11 standard defines new concepts:
- xvalue
- glvalue
- prvalue
http://stackoverflow.com/questions/3601602/what-are-rvalues-lvalues-xvalues-glvalues-and-prvalues
This is probably a consequence of move semantics.
*/
#include "common.hpp"
int main() {
#if __cplusplus >= 201103L
// TODO example
#endif
}