angular-promise.js

// more about the angular promises see on the http://habrahabr.ru/post/221111/ (doc on russian language)

// The promise need be using when a function run as async function.

var app = angular.module('app', []);
app.controller('testController',['$scope','$q',function($scope, $q){

  $scope.addOne = function(num){
    $scope.step++;
    console.log( num );
    var q = $q.defer();
    if( angular.isNumber(num)){

      setTimeout(function(){
         q.resolve(num+1)
      }, 2000)

    }else{
        q.reject('NaN')
    }

    return q.promise;
  }

  $scope.step = 0;
  $scope.myValue = 0;

  $scope.promise = $scope.addOne($scope.myValue);
  $scope.promise
  .then(function(res){
    console.log( "This is param:", res );
    return $scope.addOne(res)})
  .then(function(res){
    return $scope.addOne(res)
  })
  .then(function(res){
    console.log("This 'then' do not be running, if errors catched before!");
    $scope.myValue = res;
  }).finally(function(){
    console.log("This is 'finally' method run with any results.");
  })
  .catch(function(err){
      console.log("We catch errors on step:", $scope.step, "Error hendle is:", err);
    });

}]);

// for the IE8 "catch" need be uses as

// return doSomethingAsync()["catch"](function(err) {
//   return errorHandler(err);
// });

// end for the "IE < 9 ", the "finally" method need be use as a method catch fo the ie8.