std.concurrency : sending immutable classes

[Dejan Lekic]

On Tue, 12 Nov 2013 00:37:30 +0100, Dicebot wrote:

> Minimized repro:
> 
> import std.variant;
> 
> class A {}
> 
> void main()
> {
>      Variant v = new immutable A();
>      auto x = v.get!(immutable A)();  // triggers assert
> }
> 
> One simple question - did this ever work? :) Because passing immutable
> aggregate messages is sometimes sold as one of "proper"
> usage scenario of std.concurrency and if it was never actually
> implemented, that is damn sad. I have started to investigate this
> scenario because of question on topic in #d @ freenode.

Looks like Variant works only with implicitly convertible types.

In this case this fails:
assert(isImplicitlyConvertible!(immutable(A), A));