AngularJS Example:

HTML

<div ng-app="todoApp">
  <h2>Todo</h2>
  <div ng-controller="TodoController">
    <span>{{remaining()}} of {{todos.length}} remaining</span>
    [ <a href="" ng-click="archive()">archive</a> ]
    <ul class="unstyled">
      <li ng-repeat="todo in todos">
        <input type="checkbox" ng-model="todo.done">
        <span class="done-{{todo.done}}" ng-class="myfunction()">{{todo.text}}</span>
      </li>
    </ul>
    <form ng-submit="addTodo()">
      <input type="text" ng-model="todoText"  size="30"
             placeholder="add new todo here">
      <input class="btn-primary" type="submit" value="add">
    </form>
                 <div id="message"></div>
  </div>
</div>

CSS

</style> <!-- Ugly Hack due to jsFiddle issue: http://goo.gl/BUfGZ --> 
<link rel="stylesheet" href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.0.4/css/bootstrap-combined.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.3.0-beta.19/angular.min.js"></script>
<style>
.done-true {
  text-decoration: line-through;
  color: grey;
}

JavaScript

angular.module('todoApp', [])
  .controller('TodoController', ['$scope', function($scope) {
    $scope.todos = [
      {text:'learn angular', done:true},
      {text:'build an angular app', done:false},
      {text:'build an angular app that is slow', done:false},
      {text:'Try fixing that app', done:false},
      {text:'post a question on SO', done:false}
    ];

    $scope.addTodo = function() {
      $scope.todos.push({text:$scope.todoText, done:false});
      $scope.todoText = '';
    };

    $scope.remaining = function() {
      var count = 0;
      angular.forEach($scope.todos, function(todo) {
        count += todo.done ? 0 : 1;
      });
      return count;
    };
      var i = 0;
      $scope.myfunction = function(){
          console.log("function called");
          document.getElementById("message").innerHTML = "ng-class got evaluated " + i++ +" times";
      }
    $scope.archive = function() {
      var oldTodos = $scope.todos;
      $scope.todos = [];
      angular.forEach(oldTodos, function(todo) {
        if (!todo.done) $scope.todos.push(todo);
      });
    };
  }]);