Esprima (esprima.org) is an educational ECMAScript (also popularly known as JavaScript) parsing infrastructure for multipurpose analysis. It is also written in ECMAScript.

Esprima is created and maintained by Ariya Hidayat (Twitter: @ariyahidayat), with the help of many contributors.

Features

• Supports ECMAScript 5.1 with an experimental branch for ES.Next/Harmony
• Sensible format for the abstract syntax tree (AST), compatible with Mozilla Parser API
• Heavily tested (> 500 unit tests with solid 100% code coverage)
• Optional tracking of syntax node location (index-based and line-column)
• Blazing fast, up to 3x faster than UglifyJS parse-js (speed comparison)

Esprima runs on web browsers (IE 6+, Firefox 1+, Safari 3+, Chrome 1+, Konqueror 4.6+, Opera 8+) as well as Node.js.

Use-cases

• Smart editing: outline view, content assist
• Source code modification: Esmorph, Code Painter, node-falafel
• Code coverage analysis: node-cover, coveraje, CoverJS
• Code generation: escodegen
• Documentation tool: JFDoc, JSDuck
• Source-to-source compilation: Marv, LLJS, Harmonizr

Questions?

• Documentation
• Issue tracker: known problems and future plans
• Mailing list
• Contribution guide

Feedback and contribution are welcomed!

License

Copyright (C) 2012, 2011 Ariya Hidayat and other contributors.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.

• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.