angular.js/src/ng/directive/ngInit.js

'use strict';

/**
 * @ngdoc directive
 * @name ng.directive:ngInit
 * @restrict AC
 *
 * @description
 * The `ngInit` directive allows you to evaluate an expression in the
 * current scope.
 *
 * <div class="alert alert-error">
 * The only appropriate use of `ngInit` is for aliasing special properties of
 * {@link api/ng.directive:ngRepeat `ngRepeat`}, as seen in the demo below. Besides this case, you
 * should use {@link guide/controller controllers} rather than `ngInit`
 * to initialize values on a scope.
 * </div>
 *
 * @priority 450
 *
 * @element ANY
 * @param {expression} ngInit {@link guide/expression Expression} to eval.
 *
 * @example
   <doc:example>
     <doc:source>
   <script>
     function Ctrl($scope) {
       $scope.list = [['a', 'b'], ['c', 'd']];
     }
   </script>
   <div ng-controller="Ctrl">
     <div ng-repeat="innerList in list" ng-init="outerIndex = $index">
       <div ng-repeat="value in innerList" ng-init="innerIndex = $index">
          <span class="example-init">list[ {{outerIndex}} ][ {{innerIndex}} ] = {{value}};</span>
       </div>
     </div>
   </div>
     </doc:source>
     <doc:scenario>
       it('should alias index positions', function() {
         expect(element('.example-init').text())
           .toBe('list[ 0 ][ 0 ] = a;' +
                 'list[ 0 ][ 1 ] = b;' +
                 'list[ 1 ][ 0 ] = c;' +
                 'list[ 1 ][ 1 ] = d;');
       });
     </doc:scenario>
   </doc:example>
 */
var ngInitDirective = ngDirective({
  priority: 450,
  compile: function() {
    return {
      pre: function(scope, element, attrs) {
        scope.$eval(attrs.ngInit);
      }
    };
  }
});