import std.stdio;

import std.variant;

​

alias Message = Algebraic!(string, int, This[]);

​

auto send(T, M)(T obj, M message) { return obj.dispatch(Message(message)); }

auto send(T, MS...)(T obj, MS messages) if(MS.length > 1) {

    Message[] msg;

    foreach(m; messages) msg ~= Message(m);

    obj.send(msg);

}

​

class Foo {

    void dispatch(Message msg) {

        msg.visit!(

            (string x) => writefln("string: %s", x),

            (int x) => writefln("integer: %s", x),

            x => writefln("unsupported: %s", x)

        );

    }

}

​

void main() {

    Foo foo = new Foo;

    foo.send("hello");

    foo.send(123);

    foo.send("hello", 123);

}