Synax

Synax is a custom scripting language that transpiles to JavaScript. You write Synax source; the synax CLI compiles it down to plain, readable JavaScript.

The language is still being designed — the authoritative description of its grammar and semantics lives in SPEC.md. There is also synax.html: a single-file docs page with a live in-browser playground (the whole compiler is inlined — open it, no server needed).

Status

The pipeline is implemented end to end: source is lexed, parsed into an AST, and compiled to JavaScript. See SPEC.md §9 for what is deliberately out of scope.

Two semantics were decided while building the code generator:

• for i in 1..5 is inclusive of the upper bound (compiles to i <= 5).
• + keeps JavaScript's coercion, so "n=" + 5 concatenates rather than erroring.

Requirements

• Bun — package manager, test runner, and runtime

No external dependencies are used; everything runs on the Bun standard library.

Install

The package ships a synax binary and a typed library API:

bun add synax          # or: npm install synax

Compile a file with the CLI:

synax program.snx                # prints JavaScript to stdout
synax examples/loop.snx          # ships with the package

Or use it from code:

import { generate, Lexer, Parser } from "synax";

const source = 'print "Hello, World!"';
const js = generate(new Parser(new Lexer(source).tokenize()).parse());

Getting started (from source)

bun install                       # install dependencies (none yet)
bun test                          # run the test suite
bun run src/cli.ts <file>         # compile a Synax source file to stdout
bun run src/cli.ts examples/loop.snx
bun run build                     # bundle the CLI and library into dist/
bun run docs                      # regenerate synax.html (docs + playground)

The compiler prints JavaScript to stdout and diagnostics to stderr, exiting non-zero on a lexer, parser, or file error, so it works in a shell pipeline. Diagnostics point at the source:

examples/bad.snx:1:7: error: Unexpected character "@"
  1 | print @
    |       ^

Set SYNAX_DEBUG=1 to include a stack trace for an internal compiler error.

There is also a bun run build script that bundles the CLI into dist/.

Project layout

| Path | Purpose | | ---------------- | ------------------------------------ | | src/lexer.ts | Source text → tokens | | src/ast.ts | AST node type definitions | | src/parser.ts | Tokens → AST | | src/codegen.ts | AST → JavaScript | | src/diagnostics.ts | Positioned errors → code frames | | src/cli.ts | Command-line entrypoint | | src/index.ts | Public API re-exports | | examples/ | Sample .snx programs | | tests/ | Test suite (bun test) | | SPEC.md | Language specification | | synax.d.ts | Type declarations for the published package |