javascript, object, passing function as arguments with arguments- angular, jquery concept basic misunderstanding

Question

I am trying to understand what i am really doing, since i feel i am lack of something. Could you please point me somewhere or confirm my mis/understanding?

request.then(function(response) {
        updateCurrentUser(response.data.data);
        currentUser.isAuthenticated();
      });

Is basically this?

request = {
    then : function (foo){
        foo("first")
    } }

request.then(function (response) { console.log(response) ; });

If you see full code here#35 and here#63

directive:

    AuthenticationService.login($scope.user.email, $scope.user.password).then(function(loggedIn) {
      if ( !loggedIn ) {
        $scope.authError = "Login failed.  Please check your credentials and try again.";
      }
    });

AuthenticationService as factory:

login: function(email, password) {
  var request = $http.post('http://', {email: email, password: password});
  return request.then(function(response) {
    updateCurrentUser(response.data.data);
    return currentUser.isAuthenticated();
  });

},

The thing i don't understand is how come that the value of loggedIn variable is equal to the value what statement return currentUser.isAuthenticated(); returning AND NOT equal to the then(function(response) of original as i am returning promise from AuthenticationService. And how this could be accomplished regarding to the examples above?

Thank you.

Are you asking how a variable foo can be passed to .then(function(foo) {? For such functionality you'll need a little more advanced function: jsfiddle.net/XaYXY. — pimvdb
– pimvdb, Commented Dec 28, 2012 at 15:16
hmm..not. In request.then(function(response) .. in response have lets say value "A". Then i return that request and do again request.then(function(loggedIn) and now in loggedIn have value "B" ..regarding to the what currentUser.isAuthenticated() returning...how come? — Jakub Kuchar
– Jakub Kuchar, Commented Dec 28, 2012 at 15:46

Stan · Accepted Answer · 2012-12-28 15:29:55Z

2

I think the problem with conception arises from the fact that you overlooked the return statement. What AuthenticationService.login does is actually a closure with predefined request, so you can imagine that login is replaced with its return value request.then(function(response) {.... Then you can simply deduce that entire code row is:

AuthenticationService.login($scope.user.email, $scope.user.password).then(
function(response)
{
    updateCurrentUser(response.data.data);
    return currentUser.isAuthenticated();
}).then(
function(loggedIn)
{
  ...

This way you may see that result from response should occur as input for the next step with login check.

answered Dec 28, 2012 at 15:29

Stan

8,77810 gold badges64 silver badges107 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Jakub Kuchar Over a year ago

heck, yeah maybe .. but i still don't get it this way. Could you please be more verbose?

Jakub Kuchar Over a year ago

hell, yeah i got it :

Because calling then api of a promise returns a new derived promise, it is easily possible to create a chain of promises:

and following works:

$http.get('http://').then(function(greet) {       console.log(greet);     return "something else"     }).then(function(greet2){console.log(greet2);});

Collectives™ on Stack Overflow

javascript, object, passing function as arguments with arguments- angular, jquery concept basic misunderstanding

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related