coord-e/mlml

---

coord-e/mlml.json

{
  "createdAt": "2019-04-04T07:24:20Z",
  "defaultBranch": "develop",
  "description": "self-hosted compiler for a subset of OCaml",
  "fullName": "coord-e/mlml",
  "homepage": "",
  "language": "OCaml",
  "name": "mlml",
  "pushedAt": "2019-06-12T13:36:31Z",
  "stargazersCount": 51,
  "topics": [
    "compiler",
    "ocaml",
    "self-hosted"
  ],
  "updatedAt": "2025-03-13T21:48:37Z",
  "url": "https://github.com/coord-e/mlml"
}

mlml

mlml is a self-hosted toy compiler for a tiny subset of OCaml.

a detailed description can be found in my blog post (in Japanese): 自作OCamlコンパイラでセルフホストした - molecular coordinates

roadmap

• basic arithmetic
• variables
• if-then-else
• functions
  • recursion
  • mutual recursion
  • closure
  • currying
• tuples
• variants
• records
• pattern matching
• structual comparison
• primitive types
  • string
  • list
  • bytes
  • array
• formatted output with Printf
• modules
  • definition
  • aliases
  • open
  • dune-like bundler
• self-hosting!
• exceptions
• type checker & type inference

self hosting

mlml is self-hosted. i.e. mlml can compile itself.

./dev/exec.sh ./dev/self_host.sh

To obtain build artifacts, pass a path to local directory as below. You will see compiled binaries under ./self_host.

mkdir self_host
./dev/exec.sh ./dev/self_host.sh ./self_host

limitations

• external definitions are only available for functions
• all modules and paths are statically-resolved
• all custom oeprators are left-associative
• function keyword does not make an expression

development

If you have docker installed in your system, simply run

./dev/start.sh

to start the development.

You can run tests manually by running the following command:

./dev/exec.sh dune runtest

thanks

The code and algorithm in parser and lexer is strongly inspired by ushitora-anqou/aqaml