given ```D struct COLOR { float r, g, b, a; // a is alpha (opposite of transparency) }
auto red = COLOR(1,0,0,1); auto green = COLOR(0,1,0,1); auto blue = COLOR(0,0,1,1); auto white = COLOR(1,1,1,1); //etc ``` is there a way to do: ```D auto myColor = GREY!(0.5); // where GREY!(0.5) becomes COLOR(0.5, 0.5, 0.5, 1.0); ```