I am experimenting with Promise from ES6, but I can't find any alternative to complete as in jQuery ajax. I need to execute function after all the registered handlers with "then".
Thanks!
I am experimenting with Promise from ES6, but I can't find any alternative to complete as in jQuery ajax. I need to execute function after all the registered handlers with "then".
Thanks!
As mentioned by Bergi, what you want is the disposer pattern. Your central conception of a promise appears to be a bit off, and I think that is making this harder for you to reason about. When you call .then
, you are not conceptually "attaching a handler", you are creating a new promise that will by definition resolve after all of its .then
handlers have run.
Given your central issue based on code like this:
// a.js
module.exports = function(){
// Where 'Promise.resolve()' is a stand in for your ajax.
return Promise.resolve()
.then(function(){
// Want this to run after 'B'.
});
}
// b.js
var makePromise = require('./a');
module.exports = function specialMakePromise(){
return makePromise().then(function(){
// Should run first.
});
}
They will always run in the wrong order, because by definition, the .then
handler from a.js
must run and complete before the .then
handler from b.js
.
One way to approach this problem would instead to structure your code like this:
// a.js
module.exports = function(callback){
return Promise.resolve()
.then(callback)
.then(function(){
// Want this to run after 'B'.
});
}
// b.js
var makePromise = require('./a');
module.exports = function specialMakePromise(){
return makePromise(function(){
// Should run first.
});
}