multiple_return_values.zig

// PSEUDOCODE!

fn imm8(pins: u64, ticks: u64, pc: u16, tick_func: TickFunc) pins: u64, ticks: usize, pc: u16, data: u8 {
    pins, ticks, data = memRead(pins, ticks, pc, tick_func);
    return pins, ticks, pc +% 1, data;
}

fn memRead(pins: u64, ticks: u64, addr: u16, tick_func: TickFunc) pins: u64, ticks: usize, data: u8 {
    pins, ticks = tick(setAddr(pins, addr), ticks, 3, MREQ|RD, tick_func);
    return pins, ticks, getData(pins);
}

fn tick(pins: u64, ticks: usize, num_ticks: usize, ctrl_pins: u64, tick_func:) pins: u64, ticks: usize {
    pins = tick_func(num_ticks, (pins & ~CtrlPinMask) | ctrl_pins);
    return pins, ticks + num_ticks;
}

with_state.zig

fn imm8(state: *State) u8 {
    const data = memRead(state, state.pc);
    state.pc +%= 1;
    return data;
}

fn memRead(state: *State, addr: u16) u8 {
    state.pins = setAddr(state.pins, addr);
    tick(state, 3, MREQ|RD);
    return getData(pins);
}

fn tick(state: *State, num_ticks: usize, ctrl_pins) void {
    state.pins = state.tick_func(num_ticks, (state.pins & ~CtrlPinMask) | ctrl_pins);
    state.ticks += num_ticks;
}