js-xpath

js-xpath

An XPath Parser/Generator for JavaScript using the Jison parser/generator.

Demo

See the xpath.html file for a very simple usage for parsing xpath expressions.

Usage

First include the libraries and xpath.js and models.js files in your document. Then try the following to get started.

var expr = "/some/xpath/expression"
var parsed = xpath.parse(expr);
var regenerated = parsed.toXPath();

For examples of supported expressions, see the tests!

models.js provides a default xpathmodels which does not support the hashtag preprocessor. If you want to support hashtags within xpaths, you can use:

hashtagConfig = {
  isValidNamespace: function(namespace),
  hashtagToXPath: function(hashtag),
  toHashtag: function(expr)
}
xPathModels = XPathModels(hashtagConfig)

hashtags use the format #namespace/arbitrarily/long/path and do not support filtering

Tests

• Open test/tests.html to run tests (must be serving all files in the library).
• Individual tests are found in test/parserTests.js and test/generatorTests.js

Known Limitations

• Filter expressions are not supported due to a known bug in jison.
• See the failing tests for examples of expressions that are known not to work.

Code Structure

File	Content
dist/	contains a browser-ready build of the parser
src/jison/	contains the jison parser files.
src/lib/	external libraries that the parser depends on.
src/main.js	the entry point for non-browser users.
src/models.js	the underlying models used in parsing.
src/parser.js	the jison built parser file, do not edit manually.
test/	qunit tests for the parser and generator.

Build

This is built using jison. To build the parser file yourself run:

$ npm run build - This will build both the distribution (browserify) package in dist/ and rebuild the Jison parser (src/parser.js) from the src/jison/ files. $ npm run jison - Rebuild parser.js from the Jison specification files. $ npm run dist - Rebuild the browser friendly distribution from the current source files.

For more information on jison see the jison project website at: http://zaach.github.com/jison/.