Re: Encapsulate return value in scoped

[Yuxuan Shui via Digitalmars-d-learn]

On Thursday, 11 June 2015 at 08:48:22 UTC, Yuxuan Shui wrote:

Is there a way to encapsulate return value into scoped?

Say I have a function that returns a new object:

X new_x(T t...) {
    //Super complex input processing
    return new X(something);
}

And I want to encapsulate the result using scoped, is that possible? Can I just do:

    return scoped!X(something).
?

If I understand correctly, the data will be blitted, but the destructor will be called, so the returned object will be in invalid state.

It's even weirder than I thought, this:

import std.stdio,
       std.typecons;
class A {
        int b;
        ~this() {
                writeln("Des");
        }
        this(int x) {
                b=x;
                writeln("Cons");
        }
}
auto x() {
        A x = scoped!A(10);
        writeln(x.b);
        writeln("Return x");
        return x;
}
void main() {
        auto tx = x();
        writeln("Return main");
}

Produce output:
Cons
Des
0
Return x
Return main

Which I totally don't understand.