tree-sitter-almide

Tree-sitter grammar for the Almide programming language.

The grammar is written in Almide itself. The generator/ directory contains pure Almide code that generates grammar.js — no hand-written JavaScript. This demonstrates Almide's mission: AI can produce an entire language ecosystem in Almide.

How it works

generator/*.almd  →  almide build  →  gen-grammar binary
gen-grammar       →  execute       →  grammar.js
grammar.js        →  tree-sitter generate  →  src/parser.c

The grammar rules are modeled as an algebraic data type:

type Rule =
  | Seq(List[Rule])
  | Choice(List[Rule])
  | Repeat(Rule)
  | Str(String)
  | Ref(String)
  | Field(String, Rule)
  | PrecLeft(Int, Rule)
  | ...

fn emit(rule: Rule) -> String = match rule {
  Seq(rules) => "seq(" ++ string.join(list.map(rules, emit), ", ") ++ ")"
  Ref(name) => "$." ++ name
  ...
}

Each grammar rule is a function returning (String, Rule):

fn if_expression() -> (String, Rule) =
  ("if_expression", Seq([
    Str("if"),
    Field("condition", Ref("expression")),
    Str("then"),
    Field("consequence", Ref("expression")),
    Str("else"),
    Field("alternative", Ref("expression"))
  ]))

Features

• Full syntax coverage: modules, imports, functions, types, traits, impls, tests
• Effect system (effect fn, async)
• Pattern matching with guards
• Pipe operator (|>)
• Generic types with [] syntax
• String interpolation ("Hello, ${name}")
• Heredoc strings ("""...""")
• Result/Option constructors (ok, err, some, none)

File type

Almide source files use the .almd extension.

Usage

Rust

[dependencies]
tree-sitter-almide = { git = "https://github.com/almide/tree-sitter-almide" }
tree-sitter-language = "0.1"

use tree_sitter_almide::LANGUAGE;

let mut parser = tree_sitter::Parser::new();
parser.set_language(&LANGUAGE.into()).unwrap();
let tree = parser.parse(source, None).unwrap();

Node.js

const Parser = require("tree-sitter");
const Almide = require("tree-sitter-almide");

const parser = new Parser();
parser.setLanguage(Almide);
const tree = parser.parse(source);

Development

Regenerate grammar from Almide source

# Build the generator (requires almide compiler)
cd generator
almide build main.almd -o gen-grammar

# Generate grammar.js
./gen-grammar > ../grammar.js

# Generate parser
cd ..
tree-sitter generate

# Test
tree-sitter parse example.almd

Quick rebuild (without Almide)

tree-sitter generate
cargo test

License

MIT