Catharsis

A JavaScript parser for Google Closure Compiler type expressions.

Catharsis is designed to be:

• Accurate. Catharsis is based on a PEG.js grammar that can handle any valid type expression, no matter how complex. It uses a Mocha test suite to verify the parser's accuracy.
• Fast. Parse results are cached, so the parser is invoked only when necessary.
• Flexible. Catharsis provides both asynchronous and synchronous interfaces.

Examples

Asynchronous interface:

var catharsis = require('catharsis');

var type = '!Object';

catharsis.parse(type, {}, function(error, parsed) {
    if (error) {
        console.error('unable to parse %s: %s', type, error);
    } else {
        console.log('%j', parsed);  // {"typeName":"Object","nullable":false}
    }
});

Synchronous interface:

var catharsis = require('catharsis');

var type = '!Object';
var parsed;

try {
    parsed = catharsis.parseSync('!Object');  // {"typeName":"Object","nullable":false}
}
catch(e) {
    console.error('unable to parse %s: %s', type, e);
}

See the test/specs/ directory for more examples of Catharsis' parse results.

Synchronous interface

parse(type, opts, callback)

Parse the Closure Compiler type type, and pass the parse results to the callback.

Parameters

• type: A string containing a Closure Compiler type.
• opts: Options for parsing the type string.
  • opts.useCache: Specifies whether to use the cache of parsed types. Defaults to true.
• callback(error, parsedType): Parse results.
  • error: A description of the error, if any.
  • parsedType: An object containing the parse results.

parseSync(type, opts)

Parse the Closure Compiler type type, and return the parse results. Throws an error if the type cannot be parsed.

Parameters

• type: A string containing a Closure Compiler type.
• opts: Options for parsing the type string.
  • opts.useCache: Specifies whether to use the cache of parsed types. Defaults to true.

Returns

An object containing the parse results.

Installation

With npm:

npm install catharsis

Or without:

git clone git://github.com/hegemonic/catharsis.git

Roadmap and known issues

Take a look at the issue tracker to see what's in store for Catharsis.

Bug reports, feature requests, and pull requests are always welcome! If you're working on a large pull request, please contact me in advance so I can help things go smoothly.

Note: The parse tree's format should not be considered final until Catharsis reaches version 1.0. I'll do my best to provide release notes for any changes.

Changelog

• 0.1.1 (November 2012): Added opts argument to parse() and parseSync() methods. Note: The change to parse() is not backwards-compatible with previous versions.
• 0.1.0 (November 2012): Initial release.

License

MIT license.