yld

A JavaScript promises alternative, under the MIT License.

Concept :

yld (pronounced "yielded") is tool based on that keyword.

Contrary to promises, which grow to declare a lot of functions to disorganize your code, yld allows you to execute instructions written in a linear list.

Each yield pauses the process and allows to retrieve a response from another function ... could easily be compared to a promise.then().

The yld function :

var yielded = yld(closure);
yielded(/* closure arguments */);

The closure structure :

Create a step :

var closure;

closure = function () {
    yield; // this makes a step
};

Retrieve a response form an other scope :

var closure

closure = function () {
    var response;

    response = yield;
};

The closure properties :

Object this.parent

The parent yielded scope (parent.send() & parent.yld()), if current scope is created by this.yld(), else returns undefined

String set this.error()

Kills immediately the current process

var closure;

closure = function () {
    this.error = 'error message'; // throws the error message
    yield; // unreached point
};

Function this.send()

Send variables to the next yield response

var closure;

closure = function () {
    var response;

    this.send(123);
    response = yield; // response is 123
};

Function this.yld()

Your this context knows yld as internal method

var closure;

closure = function () {
    var yielded, response;
    
    yielded = this.yld(function (/* args */) {
        // here, the this.parent.send() is used to send a response to the parent scope
        this.parent.send(123);
    });
    
    response = yield yielded(/* args */); // response is 123
};

Requirements :

yield keyword support ES5 Object methods