Reference counted containers prototype

[Andrej Mitrovic]

On 12/27/11, Andrei Alexandrescu <SeeWebsiteForEmail at erdani.org> wrote:
> It actually does, as per the unittests. Even if it currently does by
> @property being too lax, it should continue to work.

It actually doesn't:

struct FooImpl
{
    int _x;
    @property int x() { return _x; }
    @property void x(int val) { _x = val; }

    auto dup() { return FooImpl(); }
    auto dispose() { }
}

void main()
{
    RefCounted!FooImpl foo;
    foo.x = 1;  // NG
}

Sure you could make a property return ref, but that's circumventing
the setter and allowing direct access to the field from client-code.
I've ran into this issue before when playing with opDispatch but I
couldn't figure out a workaround.

>
>> or opBinary,
>
> Should work, as operators are just translated to regular methods.
>
>> or
>> opOpAssign.
>
> Should work.
>

Doesn't seem to work:

struct FooImpl
{
    auto opBinary(string op)(int val) { return this; }
    void opOpAssign(string op)(int val) { }
    auto dup() { return FooImpl(); }
    auto dispose() { }
}

void main()
{
    RefCounted!FooImpl foo;
    auto f = foo + 1;  // ng
    foo += 1;  // ng
}

> So construction of objects
> needs to be handled by RefCounted itself - e.g. by forwarding
> constructor parameters.

But it doesn't do that currently?