Cthulhu language

A strongly-typed language that compiles into PHP

Installation

Using a pre-built phar

1. Download the cthulhu.phar executable from the latest release
2. chmod 755 cthulhu.phar
3. mv cthulhu.phar /usr/local/bin/cthulhu

Building from source

1. Clone this repository
2. In the repository root folder, run composer dump-autoload
3. Access the CLI by running php cli/cli.php. Or make the program available system-wide by something like ln -s `pwd`/bin/cthulhu.php /usr/local/bin/cthulhu

Example

A simple program looks like this:

use ::Io;

#[entry]
fn main() -> () {
  Io::println("hello world");
}

And compiles to the following PHP:

<?php

namespace Hello {
  function main() {
    print("hello world\n");
  }
}

namespace {
  \Hello\main();
}

Name capitalization

• Modules and types use PascalCase
• Function and variable names use camelCase

These capitalization rules are enforced by the language.

TODO

• Basic parsing
• Variable name resolution across module boundaries
• Generate and output PHP code from IR
• Pretty error reporting
• PHP AST rewriter library
• Basic function inlining optimization
• Basic dead-code elimination optimization
• Constant folding optimization
• Type name resolution
• Generic functions
• Pretty multi-line error snippets
• Module dependency linearized and cycle detection
• The Maybe type
• The List type
• Floating point numbers
• Pattern matching
• Recursion
• Tail call optimization
• Closures
• Extensible records
• Inference of record constraints