Re: Will a const object be moved on return?
Am 29.09.2011 20:02, schrieb Martin B.:
Isn't this something that could be improved in a future version of the
standard? C++ already considers a local l-value as an r-value on return,
wouldn't it make sense to "ignore" the constness? After all, the object
*is* gonna be destructed right away, and for it's dtor, the constness is
irrelevant (or so I like to think).
This is an interesting idea and looks doable. For copyable types like
strings this would be purely an optimization advantage (but a reasonable
one, don't get me wrong here). Even more interesting is that this would
also work for automatic and const, but move-only objects, e.g. when
using std::unique_ptr as in the following example:
std::unique_ptr<const X> source() {
const std::unique_ptr<const X> p(...);
... // Work on p, but forbid *all* mutating operations.
return p;
}
Greetings from Bremen,
Daniel Kr?gler
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