JavaScript native Promise() without callback

Question

Look at this jQuery code:

var promise = new Deferred(),
    some;

some = function(promise) {
    // do cool things

    promise.resolve();
};

promise.then(         


        

Answer 1

Here's a basic implementation that would preserve your application flow as-is.

Do not use this in real life - you'd be missing out on throw safety (thanks to @BenjaminGruenbaum for the hint).

var MyDeferred = function() {
    var _resolve,
        _reject,
        capturedPromise = new Promise(function(resolve, reject){
            _resolve = resolve;
            _reject  = reject;
        });

    return {
        'resolve' : _resolve,
        'reject'  : _reject,
        'then'    : function() { capturedPromise.then.apply(capturedPromise, arguments); },
        'catch'   : function() { capturedPromise.catch.apply(capturedPromise, arguments); }
    }
};

Answer 2

The execution flow would be a little different, but basically work the same way:

function some(resolve, reject) {
    resolve();
}

var promise = new Promise(some);

promise.then(/*  callback cool things   */);

Instead of some getting passed the promise itself, it gets passed the resolve and reject functions. So, the dependency is just the other way round.