uzn/src/main.zig

const std = @import("std");

pub fn main() !void {
    var gpa = std.heap.GeneralPurposeAllocator(.{}){};
    defer _ = gpa.deinit();
    const allocator = gpa.allocator();

    var uxn = Uxn{
        .mem = try allocator.alloc(u8, 0xFFFF),
        .ws = try allocator.alloc(u8, 0xFF),
        .rs = try allocator.alloc(u8, 0xFF),
        .wsp = 0,
        .rsp = 0,
        .pc = 0x0100,
    };
    defer allocator.free(uxn.mem);
    defer allocator.free(uxn.ws);
    defer allocator.free(uxn.rs);

    while (true) uxn.loop();
}

pub const Uxn = struct {
    mem: [0xFFFF]u8,
    // ws: [0xFF]u8,
    // rs: [0xFF]u8,
    // wsp: u8,
    // rsp: u8,
    ws: Stack,
    rs: Stack,
    pc: u16,

    const Stack = struct {
        s: *[0xFF]u8,
        sp: *u8,

        pub fn peek(self: *Stack, comptime T: type) T {
            return switch (T) {
                u8 => self.s[self.sp],
                u16 => @intCast(self.s[self.sp]), // but actually do the conversion
                else => unreachable,
            };
        }

        pub fn poke(self: *Stack, comptime T: type, v: T) void {
            switch (T) {
                u8 => self.s[self.sp] = v,
                u16 => {},
                else => unreachable,
            }
        }

        pub fn pop(self: *Stack, comptime T: type) T {
            switch (T) {
                u8 => {
                    self.sp -%= 1;
                    return self.s[self.sp +% 1];
                },
                u16 => {
                    self.sp -%= 2;
                    return self.s[self.sp +% 1];
                },
                else => unreachable,
            }
        }

        pub fn push(self: *Stack, comptime T: type, v: T) void {
            switch (T) {
                u8 => {
                    self.sp +%= 1;
                    self.s[self.sp] = v;
                },
                u16 => {
                    self.sp +%= 2;
                    self.s[self.sp] = v;
                },
                else => unreachable,
            }
        }
    };

    pub fn loop(self: *Uxn) void {
        switch (self.mem[self.pc]) {
            0x00 => {}, // BRK
            0x01 => inc(&self.ws, u8, false), // INC
            0x02 => pop(&self.ws, u8, false), // POP
            0x03 => nip(&self.ws, u8, false), // NIP
            0x04 => swp(&self.ws, u8, false), // SWP
            0x05 => rot(&self.ws, u8, false), // ROT
            0x06 => dup(&self.ws, u8, false), // DUP
            0x07 => ovr(&self.ws, u8, false), // OVR
            0x08 => equ(&self.ws, u8, false), // EQU
            0x09 => neq(&self.ws, u8, false), // NEQ
            0x0A => gth(&self.ws, u8, false), // GTH
            0x0B => lth(&self.ws, u8, false), // LTH
            0x0C => self.jmp(&self.ws, u8, false), // JMP
            0x0D => self.jcn(&self.ws, u8, false), // JCN
            0x0E => self.jsr(&self.ws, u8, false), // JSR
            0x0F => self.sth(false, u8, false), // STH
            0x10 => self.ldz(&self.ws, u8, false), // LDZ
            0x11 => self.stz(&self.ws, u8, false), // STZ
            0x12 => self.ldr(&self.ws, u8, false), // LDR
            0x13 => self.str(&self.ws, u8, false), // STR
            0x14 => self.lda(&self.ws, u8, false), // LDA
            0x15 => self.sta(&self.ws, u8, false), // STA
            0x16 => dei(&self.ws, u8, false), // DEI
            0x17 => deo(&self.ws, u8, false), // DEO
            0x18 => add(&self.ws, u8, false), // ADD
            0x19 => sub(&self.ws, u8, false), // SUB
            0x1A => mul(&self.ws, u8, false), // MUL
            0x1B => div(&self.ws, u8, false), // DIV
            0x1C => @"and"(&self.ws, u8, false), // AND
            0x1D => ora(&self.ws, u8, false), // ORA
            0x1E => eor(&self.ws, u8, false), // EOR
            0x1F => sft(&self.ws, u8, false), // SFT

            0x20 => {}, // JCI
            0x21 => inc(&self.ws, u16, false), // INC2
            0x22 => pop(&self.ws, u16, false), // POP2
            0x23 => nip(&self.ws, u16, false), // NIP2
            0x24 => swp(&self.ws, u16, false), // SWP2
            0x25 => rot(&self.ws, u16, false), // ROT2
            0x26 => dup(&self.ws, u16, false), // DUP2
            0x27 => ovr(&self.ws, u16, false), // OVR2
            0x28 => equ(&self.ws, u16, false), // EQU2
            0x29 => neq(&self.ws, u16, false), // NEQ2
            0x2A => gth(&self.ws, u16, false), // GTH2
            0x2B => lth(&self.ws, u16, false), // LTH2
            0x2C => self.jmp(&self.ws, u16, false), // JMP2
            0x2D => self.jcn(&self.ws, u16, false), // JCN2
            0x2E => self.jsr(&self.ws, u16, false), // JSR2
            0x2F => self.sth(false, u16, false), // STH2
            0x30 => self.ldz(&self.ws, u16, false), // LDZ2
            0x31 => self.stz(&self.ws, u16, false), // STZ2
            0x32 => self.ldr(&self.ws, u16, false), // LDR2
            0x33 => self.str(&self.ws, u16, false), // STR2
            0x34 => self.lda(&self.ws, u16, false), // LDA2
            0x35 => self.sta(&self.ws, u16, false), // STA2
            0x36 => dei(&self.ws, u16, false), // DEI2
            0x37 => deo(&self.ws, u16, false), // DEO2
            0x38 => add(&self.ws, u16, false), // ADD2
            0x39 => sub(&self.ws, u16, false), // SUB2
            0x3A => mul(&self.ws, u16, false), // MUL2
            0x3B => div(&self.ws, u16, false), // DIV2
            0x3C => @"and"(&self.ws, u16, false), // AND2
            0x3D => ora(&self.ws, u16, false), // ORA2
            0x3E => eor(&self.ws, u16, false), // EOR2
            0x3F => sft(&self.ws, u16, false), // SFT2

            0x40 => {}, // JMI
            0x41 => inc(&self.rs, u8, false), // INCr
            0x42 => pop(&self.rs, u8, false), // POPr
            0x43 => nip(&self.rs, u8, false), // NIPr
            0x44 => swp(&self.rs, u8, false), // SWPr
            0x45 => rot(&self.rs, u8, false), // ROTr
            0x46 => dup(&self.rs, u8, false), // DUPr
            0x47 => ovr(&self.rs, u8, false), // OVRr
            0x48 => equ(&self.rs, u8, false), // EQUr
            0x49 => neq(&self.rs, u8, false), // NEQr
            0x4A => gth(&self.rs, u8, false), // GTHr
            0x4B => lth(&self.rs, u8, false), // LTHr
            0x4C => self.jmp(&self.rs, u8, false), // JMPr
            0x4D => self.jcn(&self.rs, u8, false), // JCNr
            0x4E => self.jsr(&self.rs, u8, false), // JSRr
            0x4F => self.sth(true, u8, false), // STHr
            0x50 => self.ldz(&self.rs, u8, false), // LDZr
            0x51 => self.stz(&self.rs, u8, false), // STZr
            0x52 => self.ldr(&self.rs, u8, false), // LDRr
            0x53 => self.str(&self.rs, u8, false), // STRr
            0x54 => self.lda(&self.rs, u8, false), // LDAr
            0x55 => self.sta(&self.rs, u8, false), // STAr
            0x56 => dei(&self.rs, u8, false), // DEIr
            0x57 => deo(&self.rs, u8, false), // DEOr
            0x58 => add(&self.rs, u8, false), // ADDr
            0x59 => sub(&self.rs, u8, false), // SUBr
            0x5A => mul(&self.rs, u8, false), // MULr
            0x5B => div(&self.rs, u8, false), // DIVr
            0x5C => @"and"(&self.rs, u8, false), // ANDr
            0x5D => ora(&self.rs, u8, false), // ORAr
            0x5E => eor(&self.rs, u8, false), // EORr
            0x5F => sft(&self.rs, u8, false), // SFTr

            0x60 => {}, // JSI
            0x61 => inc(&self.rs, u16, false), // INC2r
            0x62 => pop(&self.rs, u16, false), // POP2r
            0x63 => nip(&self.rs, u16, false), // NIP2r
            0x64 => swp(&self.rs, u16, false), // SWP2r
            0x65 => rot(&self.rs, u16, false), // ROT2r
            0x66 => dup(&self.rs, u16, false), // DUP2r
            0x67 => ovr(&self.rs, u16, false), // OVR2r
            0x68 => equ(&self.rs, u16, false), // EQU2r
            0x69 => neq(&self.rs, u16, false), // NEQ2r
            0x6A => gth(&self.rs, u16, false), // GTH2r
            0x6B => lth(&self.rs, u16, false), // LTH2r
            0x6C => self.jmp(&self.rs, u16, false), // JMP2r
            0x6D => self.jcn(&self.rs, u16, false), // JCN2r
            0x6E => self.jsr(&self.rs, u16, false), // JSR2r
            0x6F => self.sth(true, u16, false), // STH2r
            0x70 => self.ldz(&self.rs, u16, false), // LDZ2r
            0x71 => self.stz(&self.rs, u16, false), // STZ2r
            0x72 => self.ldr(&self.rs, u16, false), // LDR2r
            0x73 => self.str(&self.rs, u16, false), // STR2r
            0x74 => self.lda(&self.rs, u16, false), // LDA2r
            0x75 => self.sta(&self.rs, u16, false), // STA2r
            0x76 => dei(&self.rs, u16, false), // DEI2r
            0x77 => deo(&self.rs, u16, false), // DEO2r
            0x78 => add(&self.rs, u16, false), // ADD2r
            0x79 => sub(&self.rs, u16, false), // SUB2r
            0x7A => mul(&self.rs, u16, false), // MUL2r
            0x7B => div(&self.rs, u16, false), // DIV2r
            0x7C => @"and"(&self.rs, u16, false), // AND2r
            0x7D => ora(&self.rs, u16, false), // ORA2r
            0x7E => eor(&self.rs, u16, false), // EOR2r
            0x7F => sft(&self.rs, u16, false), // SFT2r

            0x80 => {}, // LIT
            0x81 => inc(&self.ws, u8, true), // INCk
            0x82 => pop(&self.ws, u8, true), // POPk
            0x83 => nip(&self.ws, u8, true), // NIPk
            0x84 => swp(&self.ws, u8, true), // SWPk
            0x85 => rot(&self.ws, u8, true), // ROTk
            0x86 => dup(&self.ws, u8, true), // DUPk
            0x87 => ovr(&self.ws, u8, true), // OVRk
            0x88 => equ(&self.ws, u8, true), // EQUk
            0x89 => neq(&self.ws, u8, true), // NEQk
            0x8A => gth(&self.ws, u8, true), // GTHk
            0x8B => lth(&self.ws, u8, true), // LTHk
            0x8C => self.jmp(&self.ws, u8, true), // JMPk
            0x8D => self.jcn(&self.ws, u8, true), // JCNk
            0x8E => self.jsr(&self.ws, u8, true), // JSRk
            0x8F => self.sth(false, u8, true), // STHk
            0x90 => self.ldz(&self.ws, u8, true), // LDZk
            0x91 => self.stz(&self.ws, u8, true), // STZk
            0x92 => self.ldr(&self.ws, u8, true), // LDRk
            0x93 => self.str(&self.ws, u8, true), // STRk
            0x94 => self.lda(&self.ws, u8, true), // LDAk
            0x95 => self.sta(&self.ws, u8, true), // STAk
            0x96 => dei(&self.ws, u8, true), // DEIk
            0x97 => deo(&self.ws, u8, true), // DEOk
            0x98 => add(&self.ws, u8, true), // ADDk
            0x99 => sub(&self.ws, u8, true), // SUBk
            0x9A => mul(&self.ws, u8, true), // MULk
            0x9B => div(&self.ws, u8, true), // DIVk
            0x9C => @"and"(&self.ws, u8, true), // ANDk
            0x9D => ora(&self.ws, u8, true), // ORAk
            0x9E => eor(&self.ws, u8, true), // EORk
            0x9F => sft(&self.ws, u8, true), // SFTk

            0xA0 => {}, // LIT2
            0xA1 => inc(&self.ws, u16, true), // INC2k
            0xA2 => pop(&self.ws, u16, true), // POP2k
            0xA3 => nip(&self.ws, u16, true), // NIP2k
            0xA4 => swp(&self.ws, u16, true), // SWP2k
            0xA5 => rot(&self.ws, u16, true), // ROT2k
            0xA6 => dup(&self.ws, u16, true), // DUP2k
            0xA7 => ovr(&self.ws, u16, true), // OVR2k
            0xA8 => equ(&self.ws, u16, true), // EQU2k
            0xA9 => neq(&self.ws, u16, true), // NEQ2k
            0xAA => gth(&self.ws, u16, true), // GTH2k
            0xAB => lth(&self.ws, u16, true), // LTH2k
            0xAC => self.jmp(&self.ws, u16, true), // JMP2k
            0xAD => self.jcn(&self.ws, u16, true), // JCN2k
            0xAE => self.jsr(&self.ws, u16, true), // JSR2k
            0xAF => self.sth(false, u16, true), // STH2k
            0xB0 => self.ldz(&self.ws, u16, true), // LDZ2k
            0xB1 => self.stz(&self.ws, u16, true), // STZ2k
            0xB2 => self.ldr(&self.ws, u16, true), // LDR2k
            0xB3 => self.str(&self.ws, u16, true), // STR2k
            0xB4 => self.lda(&self.ws, u16, true), // LDA2k
            0xB5 => self.sta(&self.ws, u16, true), // STA2k
            0xB6 => dei(&self.ws, u16, true), // DEI2k
            0xB7 => deo(&self.ws, u16, true), // DEO2k
            0xB8 => add(&self.ws, u16, true), // ADD2k
            0xB9 => sub(&self.ws, u16, true), // SUB2k
            0xBA => mul(&self.ws, u16, true), // MUL2k
            0xBB => div(&self.ws, u16, true), // DIV2k
            0xBC => @"and"(&self.ws, u16, true), // AND2k
            0xBD => ora(&self.ws, u16, true), // ORA2k
            0xBE => eor(&self.ws, u16, true), // EOR2k
            0xBF => sft(&self.ws, u16, true), // SFT2k

            0xC0 => {}, // LITr
            0xC1 => inc(&self.rs, u8, true), // INCkr
            0xC2 => pop(&self.rs, u8, true), // POPkr
            0xC3 => nip(&self.rs, u8, true), // NIPkr
            0xC4 => swp(&self.rs, u8, true), // SWPkr
            0xC5 => rot(&self.rs, u8, true), // ROTkr
            0xC6 => dup(&self.rs, u8, true), // DUPkr
            0xC7 => ovr(&self.rs, u8, true), // OVRkr
            0xC8 => equ(&self.rs, u8, true), // EQUkr
            0xC9 => neq(&self.rs, u8, true), // NEQkr
            0xCA => gth(&self.rs, u8, true), // GTHkr
            0xCB => lth(&self.rs, u8, true), // LTHkr
            0xCC => self.jmp(&self.rs, u8, true), // JMPkr
            0xCD => self.jcn(&self.rs, u8, true), // JCNkr
            0xCE => self.jsr(&self.rs, u8, true), // JSRkr
            0xCF => self.sth(true, u8, true), // STHkr
            0xD0 => self.ldz(&self.rs, u8, true), // LDZkr
            0xD1 => self.stz(&self.rs, u8, true), // STZkr
            0xD2 => self.ldr(&self.rs, u8, true), // LDRkr
            0xD3 => self.str(&self.rs, u8, true), // STRkr
            0xD4 => self.lda(&self.rs, u8, true), // LDAkr
            0xD5 => self.sta(&self.rs, u8, true), // STAkr
            0xD6 => dei(&self.rs, u8, true), // DEIkr
            0xD7 => deo(&self.rs, u8, true), // DEOkr
            0xD8 => add(&self.rs, u8, true), // ADDkr
            0xD9 => sub(&self.rs, u8, true), // SUBkr
            0xDA => mul(&self.rs, u8, true), // MULkr
            0xDB => div(&self.rs, u8, true), // DIVkr
            0xDC => @"and"(&self.rs, u8, true), // ANDkr
            0xDD => ora(&self.rs, u8, true), // ORAkr
            0xDE => eor(&self.rs, u8, true), // EORkr
            0xDF => sft(&self.rs, u8, true), // SFTkr

            0xE0 => {}, // LIT2r
            0xE1 => inc(&self.rs, u16, true), // INC2kr
            0xE2 => pop(&self.rs, u16, true), // POP2kr
            0xE3 => nip(&self.rs, u16, true), // NIP2kr
            0xE4 => swp(&self.rs, u16, true), // SWP2kr
            0xE5 => rot(&self.rs, u16, true), // ROT2kr
            0xE6 => dup(&self.rs, u16, true), // DUP2kr
            0xE7 => ovr(&self.rs, u16, true), // OVR2kr
            0xE8 => equ(&self.rs, u16, true), // EQU2kr
            0xE9 => neq(&self.rs, u16, true), // NEQ2kr
            0xEA => gth(&self.rs, u16, true), // GTH2kr
            0xEB => lth(&self.rs, u16, true), // LTH2kr
            0xEC => self.jmp(&self.rs, u16, true), // JMP2kr
            0xED => self.jcn(&self.rs, u16, true), // JCN2kr
            0xEE => self.jsr(&self.rs, u16, true), // JSR2kr
            0xEF => self.sth(true, u16, true), // STH2kr
            0xF0 => self.ldz(&self.rs, u16, true), // LDZ2kr
            0xF1 => self.stz(&self.rs, u16, true), // STZ2kr
            0xF2 => self.ldr(&self.rs, u16, true), // LDR2kr
            0xF3 => self.str(&self.rs, u16, true), // STR2kr
            0xF4 => self.lda(&self.rs, u16, true), // LDA2kr
            0xF5 => self.sta(&self.rs, u16, true), // STA2kr
            0xF6 => dei(&self.rs, u16, true), // DEI2kr
            0xF7 => deo(&self.rs, u16, true), // DEO2kr
            0xF8 => add(&self.rs, u16, true), // ADD2kr
            0xF9 => sub(&self.rs, u16, true), // SUB2kr
            0xFA => mul(&self.rs, u16, true), // MUL2kr
            0xFB => div(&self.rs, u16, true), // DIV2kr
            0xFC => @"and"(&self.rs, u16, true), // AND2kr
            0xFD => ora(&self.rs, u16, true), // ORA2kr
            0xFE => eor(&self.rs, u16, true), // EOR2kr
            0xFF => sft(&self.rs, u16, true), // SFT2kr
        }
    }

    fn brk() void {}

    fn inc(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, a +% 1);
    }

    fn pop(stack: *Stack, comptime T: type, comptime keep: bool) void {
        if (keep) return;
        _ = stack.pop(T);
    }

    fn nip(stack: *Stack, comptime T: type, comptime keep: bool) void {
        _ = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, b);
    }

    fn swp(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, b);
        stack.push(T, a);
    }

    fn rot(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        const c = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, b);
        stack.push(T, c);
        stack.push(T, a);
    }

    fn dup(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, a);
    }

    fn ovr(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, a);
        stack.push(T, b);
        stack.push(T, a);
    }

    fn equ(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        if (a == b) stack.push(T, 1) else stack.push(T, 0);
    }

    fn neq(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        if (a != b) stack.push(T, 1) else stack.push(T, 0);
    }

    fn gth(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        if (a > b) stack.push(T, 1) else stack.push(T, 0);
    }

    fn lth(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        if (a < b) stack.push(T, 1) else stack.push(T, 0);
    }

    fn jmp(self: *Uxn, stack: *Stack, comptime T: type, comptime keep: bool) void {
        const addr = if (keep) stack.peek(T) else stack.pop(T);
        switch (T) {
            u8 => self.pc +%= @as(i8, @bitCast(addr)),
            u16 => self.pc = addr,
            else => unreachable,
        }
    }

    fn jcn(self: *Uxn, stack: *Stack, comptime T: type, comptime keep: bool) void {
        const cond = if (keep) stack.peek(T) else stack.pop(T);
        const addr = if (keep) stack.peek(T) else stack.pop(T);
        if (cond == 0) return;
        switch (T) {
            u8 => self.pc +%= @as(i8, @bitCast(addr)),
            u16 => self.pc = addr,
            else => unreachable,
        }
    }

    fn jsr(self: *Uxn, stack: *Stack, comptime T: type, comptime keep: bool) void {
        self.rs.push(u16, self.pc);
        const addr = if (keep) stack.peek(T) else stack.pop(T);
        switch (T) {
            u8 => self.pc +%= @as(i8, @bitCast(addr)),
            u16 => self.pc = addr,
            else => unreachable,
        }
    }

    fn sth(self: *Uxn, comptime swap: bool, comptime T: type, comptime keep: bool) void {
        const src = if (swap) self.rs else self.ws;
        const dst = if (swap) self.ws else self.rs;
        const a = if (keep) src.peek(T) else src.pop(T);
        dst.push(T, a);
    }

    fn ldz(self: *Uxn, stack: *Stack, comptime T: type, comptime keep: bool) void {
        const addr = if (keep) stack.peek(u8) else stack.pop(u8);
        switch (T) {
            u8 => stack.push(T, self.mem[addr]),
            u16 => {},
            else => unreachable,
        }
    }

    fn stz(self: *Uxn, stack: *Stack, comptime T: type, comptime keep: bool) void {
        const addr = if (keep) stack.peek(u8) else stack.pop(u8);
        const val = if (keep) stack.peek(T) else stack.pop(T);
        self.mem[addr] = val;
    }

    fn ldr(self: *Uxn, stack: *Stack, comptime T: type, comptime keep: bool) void {
        const addr = if (keep) stack.peek(u8) else stack.pop(u8);
        const val = self.mem[self.pc +% @as(i8, @intCast(addr))];
        stack.push(T, val);
    }

    fn str(self: *Uxn, stack: *Stack, comptime T: type, comptime keep: bool) void {
        const addr = if (keep) stack.peek(u8) else stack.pop(u8);
        const val = if (keep) stack.peek(T) else stack.pop(T);
        self.mem[self.pc +% @as(i8, @bitCast(addr))] = val;
    }

    fn lda(self: *Uxn, stack: *Stack, comptime T: type, comptime keep: bool) void {
        const addr = if (keep) stack.peek(u16) else stack.pop(u16);
        stack.push(T, self.mem[addr]);
    }

    fn sta(self: *Uxn, stack: *Stack, comptime T: type, comptime keep: bool) void {
        const addr = if (keep) stack.peek(u16) else stack.pop(u16);
        const val = if (keep) stack.peek(T) else stack.pop(T);
        self.mem[addr] = val;
    }

    fn dei(stack: *Stack, comptime T: type, comptime keep: bool) void {
        _ = stack;
        _ = T;
        _ = keep;
    }

    fn deo(stack: *Stack, comptime T: type, comptime keep: bool) void {
        _ = stack;
        _ = T;
        _ = keep;
    }

    fn add(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, a +% b);
    }

    fn sub(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, a -% b);
    }

    fn mul(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, a *% b);
    }

    fn div(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, a / b);
    }

    fn @"and"(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, a & b);
    }

    fn ora(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, a | b);
    }

    fn eor(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        stack.push(T, a ^ b);
    }

    fn sft(stack: *Stack, comptime T: type, comptime keep: bool) void {
        const a = if (keep) stack.peek(T) else stack.pop(T);
        const b = if (keep) stack.peek(T) else stack.pop(T);
        const right = b & 0b00001111;
        const left = (b & 0b11110000) >> 4;
        stack.push(T, (a >> right) << left);
    }
};