while promised

A small library to make asyncronous loops for Promise based functions.

You could use it as a wrapper to do polling or if you would like to loop but the function is asyncronous.

The library is actually not dependent on any Promise implementation and are only using .then of the function you provide, therefore you could use any thenable promise.

Usage

Install and check API below

Installation

Install with npm.

npm install while-promised

Require in you code.

var whilePromised = require('while-promised');
 
whilePromised(yourFunction);

Example

let cnt = 0;
 
function counter() {
    return new Promise(function(resolve, reject) {
        setImmediate(resolve, ++cnt);	
    });
}
 
// Loop while resolved until is 6
whilePromised(counter, 6)
    .then(function(value) {
        console.log('Values is: ' + value);
    });

API

This is the API of this library. The function returns a Promise and is thenable for when the loop finishes.

whilePromised(fn)
    .then(function() {
        // Do something
    });

Resolve to false

The simplest while loop for resolved value !== false.

whilePromised(fn);

This is comparable to:

var a = true;
while(a) {
    a = fn();
}

Resolve to value

Loop while resolved value !== stopVal.

whilePromised(fn, stopVal);

This is comparable to:

var a = 0;
while(a !== 10) {
    a = fn();
}

Compare function

Loop while compareFn returns true

whilePromised(fn, compareFn);

This is comparable to:

while(compareFn) {
    fn();
}

Contribute

Please do! Write in es6 and transpile to es5 with npm run build.

License

MIT © Jacob Carlsson