RReverser

function when(value, func) {
	var promise = Promise.cast(value);

	if (func) {
		promise = promise.then(function (value) {
			return Promise.cast(func(value)).then(function (newValue) {
				return newValue === undefined ? value : newValue;
			});
		});
	}

RReverser

feature	Promises	streams	generators
asynchronous (can push from inner callbacks)	true	true	false
multiple push	false	true	true
error catch	true	false	false
error forwarding	true	false	true
external dependency is a must	false	true	false

RReverser

var stream = require('stream');
var Rx = require('rx');
var util = require('util');

function ObservableStream(transform) {
	stream.Duplex.call(this, {objectMode: true});

	this.subject = new Rx.Subject();
	this.observable = transform(this.subject);
	this.subscription = null;

RReverser

// just for RequireBin
console.log = function () {
  var pre = document.createElement('pre');
  pre.textContent = Array.prototype.map.call(arguments, function (arg) {
    return typeof arg === 'object' ? JSON.stringify(arg, null, 2) : arg;
  }).join(' ');
  document.body.appendChild(pre);
};

var esprima = require('esprima-fb'), ast;

RReverser

function Template(str, data) {
	return str.replace(/\${([^}]+)}/g, (_, name) => data[name]);
}

var answer = 42;
(function () {
	var answer = 60;	
	console.log(Template('Answer is ${answer}', {answer}));
})();

RReverser

### Keybase proof

I hereby claim:

  * I am RReverser on github.
  * I am rreverser (https://keybase.io/rreverser) on keybase.
  * I have a public key whose fingerprint is 3456 B5A0 0E7F 67D8 A049  5B85 7634 8879 1722 011A

To claim this, I am signing this object:

RReverser

/*
The MIT License (MIT)

Copyright (c) 2015 Ingvar Stepanyan

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is

RReverser

#!/usr/bin/env node

var fs = require('fs');
var acorn = require('./parser');
var transform = require('./transform');
var escodegen = require('escodegen');

var filename = process.argv[2];
if (!filename) {
	console.log('Usage: transpile filename.js');

RReverser

var createChain = function (ops) {
	var chain = function () {};
	chain.__asyncOps = ops;
	return new Proxy(chain, AsyncContextHandler);
};

function AsyncAccessError() {
	TypeError.call(this, 'Can\'t perform synchronous operation on remote object.');
}

RReverser

function awaitableVersionOf(nodeFunction) {
	return (...args) => new Promise((resolve, reject) => {
		nodeFunction(
		  ...args,
		  (error, ...cbArgs) => error ? reject(error) : resolve(...cbArgs)
		);
	});
}