Montyyy 🐍

The goal of this project is to create an interpreter for Monty ByteCodes files.

The interpreter is written in the C programming language, and implements two simple data structures (a stack and a queue) using a doubly linked list.

The opcodes read from the Monty ByteCodes files will be used to execute operations against the stack or the queue.

The Monty language

Monty 0.98 is a scripting language that is first compiled into Monty byte codes (Just like Python). It relies on a unique stack, with specific instructions to manipulate it.

Monty byte code files

Files containing Monty byte codes usually have the .m extension. Most of the industry uses this standard but it is not required by the specification of the language. There is not more than one instruction per line. There can be any number of spaces before or after the opcode and its argument:

pochita@ubuntu:~/monty$ cat -e bytecodes/000.m
push 0$
push 1$
push 2$
  push 3$
                   pall    $
push 4$
    push 5    $
      push    6        $
pall$
pochita@ubuntu:~/monty$

Monty byte code files can contain blank lines (empty or made of spaces only), and any additional text after the opcode or its required argument is not taken into account:

pochita@ubuntu:~/monty$ cat -e bytecodes/001.m
push 0 Push 0 onto the stack$
push 1 Push 1 onto the stack$
$
push 2$
  push 3$
                   pall    $
$
$
                           $
push 4$
$
    push 5    $
      push    6        $
$
pall This is the end of our program. Monty is awesome!$
pochita@ubuntu:~/monty$

Usage

1. Compile the program with:

gcc -Wall -Werror -Wextra -pedantic -std=c89 *.c -o monty

2. Run monty <file>. Where file is the path to the file containing Monty byte code.

Opcodes

Opcode	Usage	Description
push	push <int>	pushes an element to the stack.
pall	pall	prints all the values on the stack, starting from the top of the stack.
pint	pint	prints the int value at the top of the stack, followed by a new line.
pchar	pchar	prints the char value at the top of the stack, followed by a new line.
pstr	pstr	prints the char values in the stack as a string, followed by a new line.
pop	pop	pops the value at the top of the stack.
swap	swap	swaps the two top elements of the stack.
add	add	adds the two top elements of the stack.
sub	sub	subs the two top elements of the stack.
div	div	divs the top element from the second top element of the stack.
mul	mul	multiplies the two top elements of the stack.
mod	mod	modulos the two top elements of the stack.
rotl	rotl	rotates the stack to the top: the top element becomes the last, and second top element becomes first.
rotr	rotr	rotates the stack to the bottom: the last element becomes the first.
stack	stack	switches to a stack data structure.
queue	queue	switches to a queue data structure.
#	#<text>	comments out all text after the #