SHIeld-Tailed Snake - Strings beHavIng somEwhat Like Tuples, and trAnsLatIon bEtween Dem

(it's shit)

Compiler for a Dynamically Typed, Expression Based, Garbage Collected Language, written in ML

This repository holds the source code and test files for the SHIT snake language, a final project for CS4410 at Northeastern University. Written by Jamin Eisenberg and Daniel Susman.

Features

• Strings and Comments
  • See Our String Library for details
• Tuples (untyped)
• First-class, recursive lambdas
• I/O (input(), print(val))
• Cheney's semi-space garbage collection
• x84_64 target architecture
• Register Allocation via Graph Coloring
• Sequencing
• Nil values

Example Program

def isPrefix(str, prefix):
    if len(prefix) > len(str): false
    else: if len(prefix) == 0: true
    else: equal(str[0], prefix[0]) && isPrefix(str[1:], prefix[1:])

def splitHelp(str, delim, acc):
    if len(str) == 0: (acc, )
    else:
        let fs = str[0], rst = str[1:] in
        if isPrefix(delim, fs):
            (acc,) ^ splitHelp(str[len(delim):], delim, "")
        else: splitHelp(rst, delim, acc ^ fs)

def split(str, delim):
    if len(str) == 0: (str,)
    else: splitHelp(str, delim, "")
    def pigLatinHelp(s):
        if len(s) == 0: ""
        else: s[0][1:] ^ s[0][0] ^ "ay " ^ pigLatinHelp(s[1:])

def pigLatin(s):
    if len(s) == 0: s
    else:
        let words = split(s, " ") in
        pigLatinHelp(words)

pigLatin("pig latin is the best way to communicate");

Usage

To build our project and run unit/integration tests,

    $ make test && ./test

To run a specific test file,

    $ make test
    $ ./output/do_pass/<file_name>.run

To view intermediate representations and state of the world through the various compilation phases,

    $ ./main -t input/do_pass/<file_name>.shit

Compiler Design Decisions

For string specific design decisions, please read DECISIONS.md.

Disclaimer

This language is experimental/educational. We don't recommend you use it in production.