esotope
ECMAScript code generator on steroids
This project has been started as a fork of escodegen with intention to speed up the original code. escodegen is a great project, however it was a constant bottleneck in our project, where we are doing a real-time JavaScript code instrumentation. When nearly 70% of the original code was rewritten, it became clear that it cannot be issued as a PR to the original repo and I decided to leave it as a standalone project. Currently esotope is x2 times faster than escodegen in node v0.10.x, and x4.5 times faster in node v0.11.x (benchmark). However in production we've seen x10 times performance gain in some cases.
Install
Node:
$ npm install esotope
Browser:
Drop esotope.js on page
<script src="esotope.js"></script>
then esotope will be available via window.esotope.
Or you can require it as the RequireJS module.
Usage
In general esotope can be used as a drop-in replacement for escodegen. So for the API-reference go to escodegen API page.
However, there are some missing features that did not fit well into new design and were sacrificed for speed:
- Comments attachment
- Source maps
So, if you need comments or source maps you should fallback to escodegen.
Also, Mozilla-specific obsolete ES6 syntax support has been removed (moz.starlessGenerator, moz.parenthesizedComprehensionBlock,
moz.comprehensionExpressionStartsWithAssignment options).
Testing
esotope inherits test suite from escodegen. To run tests (make sure you have gulp installed):
$ gulp test
Questions or suggestions?
If you have any questions, please feel free to create an issue here on github.