js_parser

A lexer and parser for JavaScript, written in Gleam.

This project is inspired by the js-tokens and glexer packages, and aims to provide a tool to build ECMA-262 syntax trees for gleam projects.

Installation

gleam add js_parser@1

Usage

someFile.js

export function someFunction() {
    let someVar;
}

The lexer can take any string and returns a list of tokens, including whitespace characters.

import js_parser

pub fn main() {
  let contents = js_parser.read_file("path/to/someFile.js")
  |> js_parser.parse
  |> io.debug
}

Should output:

[KeywordExport, CharWhitespace(" "), KeywordFunction, CharWhitespace(" "), IdentifierName("someFunction"), CharOpenParen, CharCloseParen, CharWhitespace(" "), CharOpenBrace, LineTerminatorSequence("\n"), CharWhitespace("    "), IdentifierName("let"), CharWhitespace(" "), IdentifierName("someVar"), CharSemicolon, LineTerminatorSequence("\n"), CharCloseBrace, LineTerminatorSequence("\n")]

gleam run -- --f samples/js/index.js
gleam test