fides

Promise utilities.

Collection of utilities to help with promise handling. Intended to be very lightweight.

API

fides.fromCallback(Function fn) -> Promise

Runs a function that takes a callback and returns the callback result as a promise.

Example:

var fides = require('fides');
var fs = require('fs');
 
fides.fromCallback(cb => fs.readFile('...', callback))
  .then(content => console.log(content));

fides.try(Function fn) -> Promise

Runs a function that may either throw or return a value or a promise. Returns a promise with the result of that function.

Example:

var fides = require('fides');
 
fides.try(() => {
  switch (behavior) {
    case 'sync value':  return 5;
    case 'async value': return Promise.resolve(5);
    case 'sync error':  throw new Error('error');
    case 'async error': return Promise.reject(new Error('error'));
  }
})
  .then(result => console.log(result));

fides.delay(number time, [Any value]) -> Promise

Returns a promise that resolves with an optional value after a certain time has passed. value can be a promise as well.

var fides = require('fides');
 
fides.delay(1000, 'value')
  .then(value => console.log('after 1 second: %s', value));