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

[Jesse Phillips via Digitalmars-d]

On Sunday, 6 November 2016 at 00:19:57 UTC, Chris Wright wrote:
> On Sat, 05 Nov 2016 20:15:14 +0000, Kapps wrote:
>> Admittedly I doubt I've ever tried () => { }, but given 
>> languages
>> like C# which this syntax was partially taken from(?)
>
> D had delegates of that form years before C# had short-form 
> delegates. Otherwise it would likely have followed suit.

The => comes exactly from C# and was introduced probably less 
than 2 years ago.