Get return type of a template function without instantiating it

[Nicholas Wilson via Digitalmars-d-learn]

On Tuesday, 22 November 2016 at 12:21:18 UTC, Yuxuan Shui wrote:
> Is there a way to get a template function return type with 
> instantiating it? The return type is independent of the 
> template arguments.
>
> I'm asking because there's potentially recursive template 
> instantiation if I do try to instantiate it.

Do you control the template in question's source? If so you could 
have a degenerate template type (e.g. MyTemplate!void ) that just 
returns the correct types .init

Otherwise i'm not sure you can because IIRC std.traits.ReturnType 
requires an instantiated symbol.