javascript - Looping ajax calls using deferred and promises -

i new jquery $.deferred , seems cannot understand whole bunch of stuffs regarding async processing.

let wanna loop through usernames , login them, process something, , logout(this might not necessary include in question).

if have 2 user/pass combinations, want loop through them, login them , necessary actions.

[{"username":"user1","password":"hardtoknow"},  {"username":"user2","password":"hardtoknow"}] 

and have created function based on read, although not on how works.

function login(user, pass) {     var d = $.deferred();     $.post(         'http://www.domain.com/login',         {             user: user,             passwrd: pass         }     ).done(function(s){             d.resolve(s);     }).fail(d.reject);      return d.promise(); } 

the above function login, , have function must have async request.

function settodo(user,pass) {     return login(user,pass)            .pipe(function(s){                 if (s.indexof('<li class="greeting">hello <span>' + user + '</span></li>')) {                     return $.post().....?                  }                 return set(usr, pw);            }); } 

that function above, although not complete, idea, try set todo , later function called submit or finalize todo

function submit(user, pass) {      return settodo(user, pass)             .pipe(function(s){             // $.post() here...      } } 

question, doing correctly? deferred? how loop through login credentials? tried using $.each , ajax request them, expected executed @ same time because async.

yes. overall doing right, note pipe being deprecated in favor of then.

here the documentation of then.