581 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			JavaScript
		
	
	
			
		
		
	
	
			581 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			JavaScript
		
	
	
/**
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 * Drupal's states library.
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 */
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(function ($) {
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  "use strict";
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  /**
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   * The base States namespace.
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   *
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   * Having the local states variable allows us to use the States namespace
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   * without having to always declare "Drupal.states".
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   */
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  var states = Drupal.states = {
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    // An array of functions that should be postponed.
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    postponed: []
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  };
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  /**
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   * Attaches the states.
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   */
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  Drupal.behaviors.states = {
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    attach: function (context, settings) {
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      var $states = $(context).find('[data-drupal-states]');
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      var config, state;
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      for (var i = 0, il = $states.length; i < il; i += 1) {
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        config = JSON.parse($states[i].getAttribute('data-drupal-states'));
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        for (state in config) {
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          if (config.hasOwnProperty(state)) {
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            new states.Dependent({
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              element: $($states[i]),
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              state: states.State.sanitize(state),
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              constraints: config[state]
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            });
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          }
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        }
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      }
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      // Execute all postponed functions now.
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      while (states.postponed.length) {
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        (states.postponed.shift())();
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      }
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    }
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  };
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  /**
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   * Object representing an element that depends on other elements.
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   *
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   * @param args
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   *   Object with the following keys (all of which are required):
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   *   - element: A jQuery object of the dependent element
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   *   - state: A State object describing the state that is dependent
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   *   - constraints: An object with dependency specifications. Lists all elements
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   *     that this element depends on. It can be nested and can contain arbitrary
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   *     AND and OR clauses.
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   */
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  states.Dependent = function (args) {
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    $.extend(this, { values: {}, oldValue: null }, args);
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    this.dependees = this.getDependees();
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    for (var selector in this.dependees) {
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      if (this.dependees.hasOwnProperty(selector)) {
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        this.initializeDependee(selector, this.dependees[selector]);
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      }
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    }
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  };
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  /**
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   * Comparison functions for comparing the value of an element with the
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   * specification from the dependency settings. If the object type can't be
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   * found in this list, the === operator is used by default.
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   */
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  states.Dependent.comparisons = {
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    'RegExp': function (reference, value) {
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      return reference.test(value);
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    },
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    'Function': function (reference, value) {
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      // The "reference" variable is a comparison function.
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      return reference(value);
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    },
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    'Number': function (reference, value) {
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      // If "reference" is a number and "value" is a string, then cast reference
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      // as a string before applying the strict comparison in compare(). Otherwise
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      // numeric keys in the form's #states array fail to match string values
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      // returned from jQuery's val().
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      return (typeof value === 'string') ? compare(reference.toString(), value) : compare(reference, value);
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    }
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  };
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  states.Dependent.prototype = {
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    /**
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     * Initializes one of the elements this dependent depends on.
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     *
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     * @param selector
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     *   The CSS selector describing the dependee.
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     * @param dependeeStates
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     *   The list of states that have to be monitored for tracking the
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     *   dependee's compliance status.
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     */
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    initializeDependee: function (selector, dependeeStates) {
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      var state, self = this;
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      function stateEventHandler(e) {
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        self.update(e.data.selector, e.data.state, e.value);
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      }
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      // Cache for the states of this dependee.
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      this.values[selector] = {};
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      for (var i in dependeeStates) {
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        if (dependeeStates.hasOwnProperty(i)) {
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          state = dependeeStates[i];
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          // Make sure we're not initializing this selector/state combination twice.
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          if ($.inArray(state, dependeeStates) === -1) {
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            continue;
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          }
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          state = states.State.sanitize(state);
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          // Initialize the value of this state.
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          this.values[selector][state.name] = null;
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          // Monitor state changes of the specified state for this dependee.
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          $(selector).on('state:' + state, {selector: selector, state: state}, stateEventHandler);
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          // Make sure the event we just bound ourselves to is actually fired.
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          new states.Trigger({ selector: selector, state: state });
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        }
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      }
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    },
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    /**
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     * Compares a value with a reference value.
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     *
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     * @param reference
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     *   The value used for reference.
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     * @param selector
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     *   CSS selector describing the dependee.
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     * @param state
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     *   A State object describing the dependee's updated state.
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     *
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     * @return
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     *   true or false.
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     */
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    compare: function (reference, selector, state) {
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      var value = this.values[selector][state.name];
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      if (reference.constructor.name in states.Dependent.comparisons) {
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        // Use a custom compare function for certain reference value types.
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        return states.Dependent.comparisons[reference.constructor.name](reference, value);
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      }
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      else {
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        // Do a plain comparison otherwise.
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        return compare(reference, value);
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      }
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    },
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    /**
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     * Update the value of a dependee's state.
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     *
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     * @param selector
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     *   CSS selector describing the dependee.
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     * @param state
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     *   A State object describing the dependee's updated state.
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     * @param value
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     *   The new value for the dependee's updated state.
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     */
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    update: function (selector, state, value) {
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      // Only act when the 'new' value is actually new.
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      if (value !== this.values[selector][state.name]) {
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        this.values[selector][state.name] = value;
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        this.reevaluate();
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      }
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    },
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    /**
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     * Triggers change events in case a state changed.
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     */
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    reevaluate: function () {
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      // Check whether any constraint for this dependent state is satisfied.
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      var value = this.verifyConstraints(this.constraints);
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      // Only invoke a state change event when the value actually changed.
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      if (value !== this.oldValue) {
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        // Store the new value so that we can compare later whether the value
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        // actually changed.
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        this.oldValue = value;
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        // Normalize the value to match the normalized state name.
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        value = invert(value, this.state.invert);
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        // By adding "trigger: true", we ensure that state changes don't go into
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        // infinite loops.
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        this.element.trigger({ type: 'state:' + this.state, value: value, trigger: true });
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      }
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    },
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    /**
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     * Evaluates child constraints to determine if a constraint is satisfied.
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     *
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     * @param constraints
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     *   A constraint object or an array of constraints.
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     * @param selector
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     *   The selector for these constraints. If undefined, there isn't yet a
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     *   selector that these constraints apply to. In that case, the keys of the
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     *   object are interpreted as the selector if encountered.
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     *
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     * @return
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     *   true or false, depending on whether these constraints are satisfied.
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     */
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    verifyConstraints: function (constraints, selector) {
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      var result;
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      if ($.isArray(constraints)) {
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        // This constraint is an array (OR or XOR).
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        var hasXor = $.inArray('xor', constraints) === -1;
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        for (var i = 0, len = constraints.length; i < len; i++) {
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          if (constraints[i] !== 'xor') {
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            var constraint = this.checkConstraints(constraints[i], selector, i);
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            // Return if this is OR and we have a satisfied constraint or if this
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            // is XOR and we have a second satisfied constraint.
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            if (constraint && (hasXor || result)) {
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              return hasXor;
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            }
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            result = result || constraint;
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          }
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        }
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      }
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      // Make sure we don't try to iterate over things other than objects. This
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      // shouldn't normally occur, but in case the condition definition is bogus,
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      // we don't want to end up with an infinite loop.
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      else if ($.isPlainObject(constraints)) {
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        // This constraint is an object (AND).
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        for (var n in constraints) {
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          if (constraints.hasOwnProperty(n)) {
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            result = ternary(result, this.checkConstraints(constraints[n], selector, n));
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            // False and anything else will evaluate to false, so return when any
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            // false condition is found.
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            if (result === false) { return false; }
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          }
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        }
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      }
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      return result;
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    },
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    /**
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     * Checks whether the value matches the requirements for this constraint.
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     *
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     * @param value
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     *   Either the value of a state or an array/object of constraints. In the
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     *   latter case, resolving the constraint continues.
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     * @param selector
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     *   The selector for this constraint. If undefined, there isn't yet a
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     *   selector that this constraint applies to. In that case, the state key is
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     *   propagates to a selector and resolving continues.
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     * @param state
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     *   The state to check for this constraint. If undefined, resolving
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     *   continues.
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     *   If both selector and state aren't undefined and valid non-numeric
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     *   strings, a lookup for the actual value of that selector's state is
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     *   performed. This parameter is not a State object but a pristine state
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     *   string.
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     *
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     * @return
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     *   true or false, depending on whether this constraint is satisfied.
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     */
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    checkConstraints: function (value, selector, state) {
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      // Normalize the last parameter. If it's non-numeric, we treat it either as
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      // a selector (in case there isn't one yet) or as a trigger/state.
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      if (typeof state !== 'string' || (/[0-9]/).test(state[0])) {
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        state = null;
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      }
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      else if (typeof selector === 'undefined') {
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        // Propagate the state to the selector when there isn't one yet.
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        selector = state;
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        state = null;
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      }
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      if (state !== null) {
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        // constraints is the actual constraints of an element to check for.
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        state = states.State.sanitize(state);
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        return invert(this.compare(value, selector, state), state.invert);
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      }
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      else {
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        // Resolve this constraint as an AND/OR operator.
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        return this.verifyConstraints(value, selector);
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      }
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    },
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 | 
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    /**
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     * Gathers information about all required triggers.
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     */
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    getDependees: function () {
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      var cache = {};
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      // Swivel the lookup function so that we can record all available selector-
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      // state combinations for initialization.
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      var _compare = this.compare;
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      this.compare = function (reference, selector, state) {
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        (cache[selector] || (cache[selector] = [])).push(state.name);
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        // Return nothing (=== undefined) so that the constraint loops are not
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        // broken.
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      };
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 | 
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      // This call doesn't actually verify anything but uses the resolving
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      // mechanism to go through the constraints array, trying to look up each
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      // value. Since we swivelled the compare function, this comparison returns
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      // undefined and lookup continues until the very end. Instead of lookup up
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      // the value, we record that combination of selector and state so that we
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      // can initialize all triggers.
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      this.verifyConstraints(this.constraints);
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      // Restore the original function.
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      this.compare = _compare;
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      return cache;
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    }
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  };
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  states.Trigger = function (args) {
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    $.extend(this, args);
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    if (this.state in states.Trigger.states) {
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      this.element = $(this.selector);
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      // Only call the trigger initializer when it wasn't yet attached to this
 | 
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      // element. Otherwise we'd end up with duplicate events.
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      if (!this.element.data('trigger:' + this.state)) {
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        this.initialize();
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      }
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    }
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  };
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  states.Trigger.prototype = {
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    initialize: function () {
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      var trigger = states.Trigger.states[this.state];
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      if (typeof trigger === 'function') {
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        // We have a custom trigger initialization function.
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        trigger.call(window, this.element);
 | 
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      }
 | 
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      else {
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        for (var event in trigger) {
 | 
						|
          if (trigger.hasOwnProperty(event)) {
 | 
						|
            this.defaultTrigger(event, trigger[event]);
 | 
						|
          }
 | 
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        }
 | 
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      }
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						|
 | 
						|
      // Mark this trigger as initialized for this element.
 | 
						|
      this.element.data('trigger:' + this.state, true);
 | 
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    },
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						|
 | 
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    defaultTrigger: function (event, valueFn) {
 | 
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      var oldValue = valueFn.call(this.element);
 | 
						|
 | 
						|
      // Attach the event callback.
 | 
						|
      this.element.on(event, $.proxy(function (e) {
 | 
						|
        var value = valueFn.call(this.element, e);
 | 
						|
        // Only trigger the event if the value has actually changed.
 | 
						|
        if (oldValue !== value) {
 | 
						|
          this.element.trigger({ type: 'state:' + this.state, value: value, oldValue: oldValue });
 | 
						|
          oldValue = value;
 | 
						|
        }
 | 
						|
      }, this));
 | 
						|
 | 
						|
      states.postponed.push($.proxy(function () {
 | 
						|
        // Trigger the event once for initialization purposes.
 | 
						|
        this.element.trigger({ type: 'state:' + this.state, value: oldValue, oldValue: null });
 | 
						|
      }, this));
 | 
						|
    }
 | 
						|
  };
 | 
						|
 | 
						|
  /**
 | 
						|
   * This list of states contains functions that are used to monitor the state
 | 
						|
   * of an element. Whenever an element depends on the state of another element,
 | 
						|
   * one of these trigger functions is added to the dependee so that the
 | 
						|
   * dependent element can be updated.
 | 
						|
   */
 | 
						|
  states.Trigger.states = {
 | 
						|
    // 'empty' describes the state to be monitored
 | 
						|
    empty: {
 | 
						|
      // 'keyup' is the (native DOM) event that we watch for.
 | 
						|
      'keyup': function () {
 | 
						|
        // The function associated to that trigger returns the new value for the
 | 
						|
        // state.
 | 
						|
        return this.val() === '';
 | 
						|
      }
 | 
						|
    },
 | 
						|
 | 
						|
    checked: {
 | 
						|
      'change': function () {
 | 
						|
        // prop() and attr() only takes the first element into account. To support
 | 
						|
        // selectors matching multiple checkboxes, iterate over all and return
 | 
						|
        // whether any is checked.
 | 
						|
        var checked = false;
 | 
						|
        this.each(function () {
 | 
						|
          // Use prop() here as we want a boolean of the checkbox state.
 | 
						|
          // @see http://api.jquery.com/prop/
 | 
						|
          checked = $(this).prop('checked');
 | 
						|
          // Break the each() loop if this is checked.
 | 
						|
          return !checked;
 | 
						|
        });
 | 
						|
        return checked;
 | 
						|
      }
 | 
						|
    },
 | 
						|
 | 
						|
    // For radio buttons, only return the value if the radio button is selected.
 | 
						|
    value: {
 | 
						|
      'keyup': function () {
 | 
						|
        // Radio buttons share the same :input[name="key"] selector.
 | 
						|
        if (this.length > 1) {
 | 
						|
          // Initial checked value of radios is undefined, so we return false.
 | 
						|
          return this.filter(':checked').val() || false;
 | 
						|
        }
 | 
						|
        return this.val();
 | 
						|
      },
 | 
						|
      'change': function () {
 | 
						|
        // Radio buttons share the same :input[name="key"] selector.
 | 
						|
        if (this.length > 1) {
 | 
						|
          // Initial checked value of radios is undefined, so we return false.
 | 
						|
          return this.filter(':checked').val() || false;
 | 
						|
        }
 | 
						|
        return this.val();
 | 
						|
      }
 | 
						|
    },
 | 
						|
 | 
						|
    collapsed: {
 | 
						|
      'collapsed': function (e) {
 | 
						|
        return (typeof e !== 'undefined' && 'value' in e) ? e.value : !this.is('[open]');
 | 
						|
      }
 | 
						|
    }
 | 
						|
  };
 | 
						|
 | 
						|
  /**
 | 
						|
   * A state object is used for describing the state and performing aliasing.
 | 
						|
   */
 | 
						|
  states.State = function (state) {
 | 
						|
    // We may need the original unresolved name later.
 | 
						|
    this.pristine = this.name = state;
 | 
						|
 | 
						|
    // Normalize the state name.
 | 
						|
    while (true) {
 | 
						|
      // Iteratively remove exclamation marks and invert the value.
 | 
						|
      while (this.name.charAt(0) === '!') {
 | 
						|
        this.name = this.name.substring(1);
 | 
						|
        this.invert = !this.invert;
 | 
						|
      }
 | 
						|
 | 
						|
      // Replace the state with its normalized name.
 | 
						|
      if (this.name in states.State.aliases) {
 | 
						|
        this.name = states.State.aliases[this.name];
 | 
						|
      }
 | 
						|
      else {
 | 
						|
        break;
 | 
						|
      }
 | 
						|
    }
 | 
						|
  };
 | 
						|
 | 
						|
  /**
 | 
						|
   * Creates a new State object by sanitizing the passed value.
 | 
						|
   */
 | 
						|
  states.State.sanitize = function (state) {
 | 
						|
    if (state instanceof states.State) {
 | 
						|
      return state;
 | 
						|
    }
 | 
						|
    else {
 | 
						|
      return new states.State(state);
 | 
						|
    }
 | 
						|
  };
 | 
						|
 | 
						|
  /**
 | 
						|
   * This list of aliases is used to normalize states and associates negated names
 | 
						|
   * with their respective inverse state.
 | 
						|
   */
 | 
						|
  states.State.aliases = {
 | 
						|
    'enabled': '!disabled',
 | 
						|
    'invisible': '!visible',
 | 
						|
    'invalid': '!valid',
 | 
						|
    'untouched': '!touched',
 | 
						|
    'optional': '!required',
 | 
						|
    'filled': '!empty',
 | 
						|
    'unchecked': '!checked',
 | 
						|
    'irrelevant': '!relevant',
 | 
						|
    'expanded': '!collapsed',
 | 
						|
    'open': '!collapsed',
 | 
						|
    'closed': 'collapsed',
 | 
						|
    'readwrite': '!readonly'
 | 
						|
  };
 | 
						|
 | 
						|
  states.State.prototype = {
 | 
						|
    invert: false,
 | 
						|
 | 
						|
    /**
 | 
						|
     * Ensures that just using the state object returns the name.
 | 
						|
     */
 | 
						|
    toString: function () {
 | 
						|
      return this.name;
 | 
						|
    }
 | 
						|
  };
 | 
						|
 | 
						|
  /**
 | 
						|
   * Global state change handlers. These are bound to "document" to cover all
 | 
						|
   * elements whose state changes. Events sent to elements within the page
 | 
						|
   * bubble up to these handlers. We use this system so that themes and modules
 | 
						|
   * can override these state change handlers for particular parts of a page.
 | 
						|
   */
 | 
						|
 | 
						|
  $(document).on('state:disabled', function (e) {
 | 
						|
    // Only act when this change was triggered by a dependency and not by the
 | 
						|
    // element monitoring itself.
 | 
						|
    if (e.trigger) {
 | 
						|
      $(e.target)
 | 
						|
        .prop('disabled', e.value)
 | 
						|
        .closest('.form-item, .form-submit, .form-wrapper').toggleClass('form-disabled', e.value)
 | 
						|
        .find('select, input, textarea').prop('disabled', e.value);
 | 
						|
 | 
						|
      // Note: WebKit nightlies don't reflect that change correctly.
 | 
						|
      // See https://bugs.webkit.org/show_bug.cgi?id=23789
 | 
						|
    }
 | 
						|
  });
 | 
						|
 | 
						|
  $(document).on('state:required', function (e) {
 | 
						|
    if (e.trigger) {
 | 
						|
      if (e.value) {
 | 
						|
        var $label = $(e.target).attr({ 'required': 'required', 'aria-required': 'aria-required' }).closest('.form-item, .form-wrapper').find('label');
 | 
						|
        // Avoids duplicate required markers on initialization.
 | 
						|
        if (!$label.hasClass('form-required').length) {
 | 
						|
          $label.addClass('form-required');
 | 
						|
        }
 | 
						|
      }
 | 
						|
      else {
 | 
						|
        $(e.target).removeAttr('required aria-required').closest('.form-item, .form-wrapper').find('label.form-required').removeClass('form-required');
 | 
						|
      }
 | 
						|
    }
 | 
						|
  });
 | 
						|
 | 
						|
  $(document).on('state:visible', function (e) {
 | 
						|
    if (e.trigger) {
 | 
						|
      $(e.target).closest('.form-item, .form-submit, .form-wrapper').toggle(e.value);
 | 
						|
    }
 | 
						|
  });
 | 
						|
 | 
						|
  $(document).on('state:checked', function (e) {
 | 
						|
    if (e.trigger) {
 | 
						|
      $(e.target).prop('checked', e.value);
 | 
						|
    }
 | 
						|
  });
 | 
						|
 | 
						|
  $(document).on('state:collapsed', function (e) {
 | 
						|
    if (e.trigger) {
 | 
						|
      if ($(e.target).is('[open]') === e.value) {
 | 
						|
        $(e.target).find('> summary a').trigger('click');
 | 
						|
      }
 | 
						|
    }
 | 
						|
  });
 | 
						|
 | 
						|
  /**
 | 
						|
   * These are helper functions implementing addition "operators" and don't
 | 
						|
   * implement any logic that is particular to states.
 | 
						|
   */
 | 
						|
 | 
						|
  /**
 | 
						|
   * Bitwise AND with a third undefined state.
 | 
						|
   */
 | 
						|
  function ternary(a, b) {
 | 
						|
    return typeof a === 'undefined' ? b : (typeof b === 'undefined' ? a : a && b);
 | 
						|
  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Inverts a (if it's not undefined) when invertState is true.
 | 
						|
   */
 | 
						|
  function invert(a, invertState) {
 | 
						|
    return (invertState && typeof a !== 'undefined') ? !a : a;
 | 
						|
  }
 | 
						|
 | 
						|
  /**
 | 
						|
   * Compares two values while ignoring undefined values.
 | 
						|
   */
 | 
						|
  function compare(a, b) {
 | 
						|
    return (a === b) ? (typeof a === 'undefined' ? a : true) : (typeof a === 'undefined' || typeof b === 'undefined');
 | 
						|
  }
 | 
						|
 | 
						|
})(jQuery);
 |