import std.stdio;

​

void 

main() {

    writeln;

    writeln ("Event_1");

    Event_1 event_1;

    event (event_1);

​

    writeln;

    writeln ("Event_2");

    Event_2 event_2;

    event (event_2);

}

​

struct

Event_1 {

    ushort type  = 1;

    ushort code  = 2;

    uint   value = 3;

}

​

struct

Event_2 {

    ushort type  = 1;

    ushort code  = 2;

    uint   value = 3;

    float  x = 4.0;

    float  y = 5.0;

}

​

​

void

event (EVENT) (/* R this, */ EVENT e) {

    enum REG_SIZE = (void*).sizeof; // Bytes

    pragma (msg, EVENT, " : ", EVENT.sizeof);

    pragma (msg, "REG_SIZE: ", REG_SIZE);

    static if (EVENT.sizeof == 0) {

        //

    }

    else

    static if (EVENT.sizeof <= REG_SIZE) {  //  64 bit

        _event (/* this, */ 

            * cast (REG*) &e,

            //* cast (REG*) cast (ubyte*) &e,

            //cast (REG) *(

            //  (cast (ubyte*) &e)[0..EVENT.sizeof].ptr

            //), 

            0, 

            0);

    }

    else

    static if (EVENT.sizeof <= 2*REG_SIZE) {  // 128 bit

        _event (/* this, */ 

            cast (REG) *(

                (cast (ubyte*) &e)[0..REG_SIZE].ptr

            ), 

            cast (REG) *(

                (cast (ubyte*) &e)[REG_SIZE..EVENT.sizeof].ptr

            ), 

            0);

    }

    else

        static assert (0, "Event sizeof too much");

}

​

alias REG = ulong;

​

void

_event (/* REG this, */ REG type_code_value, REG r3, REG r4) {

    //switch (type_code_value.type) {

    //    case Event.Type.GUI: gui.event (type_code_value, r3, r4); break;

    //    default:

    //}

    writeln ("type_code_value: ", type_code_value);

    writeln ("r3: ", r3);

    writeln ("r4: ", r4);

​

    Event_1 event_1;

    event_1 = * cast (Event_1*) &type_code_value;

​

    writeln ("  event_1 :", event_1);

​

    if (r3 != 0) {

        writeln ("  event_2 :", r3);

    }

}