Angular:
http://angularjs.org/
by Akram kamal
HTML
<div ng-controller="MyCtrl">
<span ng-switch on="x">
<div ng-switch-when="true" ng-include="'partial.html'"></div>
<div ng-switch-default>default</div>
</span>
</div>
<script type="text/ng-template" id="partial.html">
Content of the template.
</script>
JavaScript
var app = angular.module('myApp', []);
function MyCtrl($scope) {
$scope.x = true;
}