Re: Never called destructor

[Don]

div0 wrote:

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bearophile wrote:

div0:

    scope x = new A("x");
    y = new A("y");
    x = y;

In my opinion it's better to not reassign references of scoped objects.
In real programs where possible it's better to write boring and stupid code :-)

Bye,
bearophile

Yeah, I was thinking about that and wondering whether in fact it should
be an error and disallowed.

I use scope because I want the instance on the stack for performance,
and allowing the scope ref to be reassigned buggers things up.

also consider:

import std.stdio;

class A {
        string  _instance;

        this(string instance) {
                _instance = instance;
        }

        ~this() {
                writefln("A.~this @ 0x%x: %s", cast(void*)this, _instance);
        }
}

A test() {
        scope   x = new A("x");
        auto    y = new A("y");
        x = y;
        return y;
}

void main()
{
        scope z = test();
        writefln("main, z @ 0x%x, [%s]", cast(void*)z, z._instance);
}

output:

A.~this @ 0x962E40: y
main, z @ 0x962E40, [y]

This is clearly wrong, we are accessing a deleted object, and for some
reason we aren't getting a double delete of y, which we should.

Same as bug 3285 / bug 3516?