Peggy is a simple parser generator for JavaScript that produces fast parsers with excellent error reporting. You can use it to process complex data or computer languages and build transformers, interpreters, compilers and other tools easily.
Peggy is the successor of PEG.js.
Peggy version 1.x.x is API compatible with the most recent PEG.js release. Follow these steps to upgrade:
pegjs
(and @types/pegjs
if you're using the DefinitelyTyped type definitions - we now include type definitions as part of peggy itself).require("pegjs")
or import ... from "pegjs"
with require("peggy")
or import ... from "peggy"
as appropriate.pegjs
cli should now use peggy
instead.Online version is the easiest way to generate a parser. Just enter your grammar, try parsing few inputs, and download generated parser code.
Full documentation is available at peggyjs.org.
To get started, check out peggy, install the dependencies, and run build:
git clone https://github.com/peggyjs/peggy.git
cd peggy
npm install
(cd docs && npm install)
(cd web-test && npm install)
npm run build
npm run test:web
Please see the Contribution Guidelines for details on how to contribute code.
Peggy was originally developed by David Majda (@dmajda). It is currently maintained by Joe Hildebrand (@hildjj).
You are welcome to contribute code. Unless your contribution is really trivial you should get in touch with us first — this can prevent wasted effort on both sides.