Friday, June 1st, 2007
The Cruiser Parser Library
Dan Yoder has recently developed a small (2.5k) JavaScript library for creating top-down recursive descent LLk parsers, Cruiser.
Dan uses it himself to parse stylesheets, to support CSS3 selectors.
Here is the parser:
- with ( Parser.Operators ) {
- var g = Behaviors.Stylesheet.Grammar;
- var t = Behaviors.Stylesheet.Translator;
- // basic tokens
- g.lbrace = token('{'); g.rbrace = token('}');
- g.lparen = token(/\(/); g.rparen = token(/\)/);
- g.colon = token(':'); g.semicolon = token(';');
- // attributes
- g.attrName = token(/[\w\-\d]+/);
- g.attrValue = token(/[^;\}]+/);
- g.attr = pair(g.attrName,g.attrValue,g.colon);
- g.attrList = list(g.attr,g.semicolon,true);
- g.style = process(
- between(g.lbrace,g.attrList,g.rbrace),t.style);
- // style rules
- g.selector = token(/[^\{]+/);
- g.rule = each(g.selector,g.style);
- g.rules = process(many(g.rule),t.rules);
- // comments
- g.inlineComment = token(/\x2F\x2F[^\n]\n/);
- g.multilineComment = token(/\x2F\x2A.*?\x2A\x2F/);
- g.comments = ignore(
- any(g.inlineComment,g.multilineComment));
- // parser
- Behaviors.Stylesheet._parse = process(
- many(any(g.comments,g.rules)),t.parse);
- }
Parse away.





3.4 rating from 16 votes
now for those who have no clue what you’re talking about… what would I use this for? :-)
That would be 2.5k, plus cruiser.js (4.5k) plus Prototype 1.5.1 (21.36k) equals 28.36k.
I don’t understand why devs fail to understand how to truley use JavaScript and their Frameworks.
The code is around 17kb if you use it right.
http://www.thinkvitamin.com/features/webapps/serving-javascript-fast
http://code.google.com/p/minify/
http://www.devpro.it/php5_id_145.html
http://rakaz.nl/item/make_your_pages_load_faster_by_combining_and_compressing_javascript_and_css_files
This is a niche kind of library that I am personally *very* interested in. Thanks much for the lead, Dion.
On a related note, has anyone heard of a javascript parser that can read in an XML dtd and turn it into some kind of useable properties?
@Mike Ritchie,
Here’s a lead: http://xmljs.sourceforge.net/
Or you could try to pull it off yourself using Cruiser.