Angular

HTML

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.2.3/angular.min.js"></script>
<button add-condition="false">I shouldn't exist in the dom</button>

JavaScript

angular.module('app', [])

.directive('addCondition', function($rootScope) {
    return {
        restrict: 'A',
        compile: function (element, attr) {
          var ngIf = attr.ngIf,
              value = $rootScope.$eval(attr.addCondition);

          /**
           * Make sure to combine with existing ngIf!
           */
          if (ngIf) {
            value += ' && ' + ngIf;
          }

          attr.$set('ng-if', value);
        }
    };
});