ltx-xpath/lib/xpath.js

xpath evaluator for ltx

(function() {
  var EventEmitter, evaluate, parse,
    __bind = function(fn, me){ return function(){ return fn.apply(me, arguments); }; },
    __hasProp = {}.hasOwnProperty,
    __extends = function(child, parent) { for (var key in parent) { if (__hasProp.call(parent, key)) child[key] = parent[key]; } function ctor() { this.constructor = child; } ctor.prototype = parent.prototype; child.prototype = new ctor(); child.__super__ = parent.prototype; return child; };

  EventEmitter = require('events').EventEmitter;

  parse = require('xpath-parser').parse;

  evaluate = require('./evaluate').evaluate;

  exports.XPath = (function(_super) {
    __extends(XPath, _super);

    function XPath() {
      this.match = __bind(this.match, this);      this._expressions = {};
    }

    XPath.prototype.addExpression = function(xpath, namespaces) {
      var exp;

      exp = parse(xpath);
      exp.xpath = xpath;
      exp.namespace = namespaces;
      return this._expressions[xpath] = exp;
    };

    XPath.prototype.addListener = function(event, ns, listener) {
      var _ref;

      if (listener == null) {
        _ref = [null, ns], ns = _ref[0], listener = _ref[1];
      }
      if (this._expressions[event] != null) {
        return XPath.__super__.addListener.call(this, event, listener);
      }
      this.addExpression(event, ns);
      return XPath.__super__.addListener.call(this, event, listener);
    };

    XPath.prototype.on = XPath.prototype.addListener;

    XPath.prototype.once = function(event, ns, listener) {
      var _ref;

      if (listener == null) {
        _ref = [null, ns], ns = _ref[0], listener = _ref[1];
      }
      if (this._expressions[event] != null) {
        return XPath.__super__.once.call(this, event, listener);
      }
      this.addExpression(event, ns);
      return XPath.__super__.once.call(this, event, listener);
    };

    XPath.prototype.removeListener = function(event) {
      var res;

      res = XPath.__super__.removeListener.apply(this, arguments);
      if (!this.listeners(event).length) {
        delete this._expressions[event];
      }
      return res;
    };

    XPath.prototype.match = function(elem) {
      var event, expression, match, matched, _ref;

      matched = false;
      _ref = this._expressions;
      for (event in _ref) {
        expression = _ref[event];
        match = evaluate(expression, [elem], expression.namespace);
        if (match.length) {
          matched = true;
          this.emit(event, elem, match);
        }
      }
      return matched;
    };

    return XPath;

  })(EventEmitter);

}).call(this);