Why doesn't std.variant.visit automatically call the provided delegates?

[Nick Sabalausky via Digitalmars-d]

On 11/05/2016 04:22 PM, Adam D. Ruppe wrote:
> On Saturday, 5 November 2016 at 20:15:14 UTC, Kapps wrote:
>> That feels like it should be a compiler warning.
>
> I'm now of the opinion that the {} delegates should be deprecated
> (instead use () {} delegates)... this comes up a lot and there's a few
> other places too where it is a pain... and it isn't that worth keeping imo.

I didn't even know you could create a delegate with just {} and no 
parens. Kinda confusing since, normally, {} by itself creates a scope, 
not a delegate.