Re: Const ref and rvalues again...

[Dmitry Olshansky]

11/7/2012 9:04 PM, martin пишет:

On Wednesday, 7 November 2012 at 14:07:31 UTC, martin wrote:

C++:
void f(T& a) { // for lvalues
    this->resource = a.resource;
    a.resetResource();
}
void f(T&& a) { // for rvalues (moved)
    this->resource = a.resource;
    a.resetResource();
}

D:
void f(ref T a) { // for lvalues
    this.resource = a.resource;
    a.resetResource();
}
void f(T a) { // rvalue argument is not copied, but moved
    this.resource = a.resource;
    a.resetResource();
}

You could probably get away with a single-line overload, both in C++ and D:

C++:
void f(T& a) { // for lvalues
     // convert a to mutable rvalue reference and
     // invoke the main overload f(T&&)
     f(std::move(a));
}

D:
void f(T a) { // rvalue argument is not copied, but moved
     // the original argument is now named a (an lvalue)
     // invoke the main overload f(ref T)
     f(a);
}

Yup, and I'd like auto ref to actually do this r-value trampoline for me.

--
Dmitry Olshansky