On Sunday 21 November 2010 16:19:27 bearophile wrote:
> This D2 program shows that you can't test if a class reference wrapped with
> Rebindable is null:
>
>
> import std.typecons;
> const class Foo {}
> void main() {
> auto a = Rebindable!Foo(new Foo);
> a = new Foo;
> assert(a !is null); // err
> }
>
>
> DMD 2.050 generates:
> test.d(6): Error: incompatible types for ((a) !is (null)):
> 'Rebindable!(const(Foo))' and 'void*'
>
>
> Is this the currently correct way to do it? (It works):
>
> assert(a.get() !is null); // OK
>
> I have seen the get() method is not documented on the site, so is that a
> temporary limitation caused by the unfinished "alis this" implementation?
>
> Bye and thank you,
> bearophile
(a.get !is null) works. Why it's not documented, I don't know, and whether (a
!is null) will ever be able to work with alias this, I don't know. I just know
that (a.get !is null) currently works.
- Jonathan M Davis
