support function pointer in match method of URLRouter

[extrawurst]

this is to support the following code:

import vibe.d;

void index(HTTPServerRequest req, HTTPServerResponse res){}

shared static this()
{
    auto router = new URLRouter;
    router.match(HTTPMethod.OPTIONS,"*", &index);

    listenHTTP(new HTTPServerSettings, router);
}

without this change the compiler refuses with:

source\app.d(8): Error: function vibe.http.router.URLRouter.match (HTTPMethod method, string path, v
oid delegate(HTTPServerRequest req, HTTPServerResponse res) cb) is not callable using argument types
 (HTTPMethod, string, void function(HTTPServerRequest req, HTTPServerResponse res))

is this maybe even a compiler bug ??

[etcimon]

is this maybe even a compiler bug ??

I think the distinction between function and delegate in D is important to know and shouldn't be implicitly converted, but this does seem more convenient. You have my vote

[s-ludwig]

Hm.. forgot to submit my comment before closing the browser tab. So the compiler is behaving as designed in this case w.r.t hiding overloads defined in the base class. It's basically the same as in C++, where using HTTPRouter::match is used instead of alias as in D.