tincho

Table of Contents generated with DocToc

• FrontEnd Masters - ES6 notes
  • Proper Tail Call (PTC)
  • Function Hoisting
  • Variables
    • Temporal Dead Zone
• Rest Parameters

tincho

// requires jQuery!

const noop = () => {};
const constant = v => () => v;
const beTrue = constant(true); // () => true;
function $Ajaxify(form, ...callbacks) {

  if (typeof callbacks[0] === 'object') {
    var {
      onSuccess = noop, onError = noop, beforeSend = beTrue

tincho

var form = document.getElementById("dlFile");

form.onsubmit = function(e) {
  e.preventDefault();
  var user = form.user.value; // "mayoristas";
  var pass = form.pass.value;
  requestFile(user, pass);
  return false;
}

tincho

/**
 * @license MIT
 * @requires AngularJs 1.x
 * @author github.com/tincho
 * Tiny helper for listener deregistration on scope destroy
 * You'll have to wrap it up in a module/provider/whatever
 * (that's out of my focus)
 */
function LDisposer(scope) {
   var _list = [];

tincho

// iteration 0
// adding deep diving for key paths
// based on getProperty()
// try on tddbin.com

function copyFrom(obj) {
  const values = (...keys) => keys.map(k => getProperty(k)(obj)); 
  return { values };
}

tincho

// first iteration
// v0.1

(function(globalObject, document) {

  function randomItem(collection) {
    var index = Math.floor(Math.random() * collection.length);
    return collection[index];
  }

tincho

// alternative version using ES6 Array.from

const chunkify = (chunkSize, src) => Array.from(
  { length: Math.ceil(src.length/chunkSize) },
  (_, i) => src.slice(i * chunkSize, i * chunkSize + chunkSize)
)

tincho

// pre-ES6
function _ary(fn, arity) {
    arity = arity || 1;
    return function() {
        // could use Array.from(arguments).slice(0, arity) ?
        var args = Array.prototype.slice.call(arguments, 0, arity);
        return fn.apply(null, args);
    };
}

tincho

function getHeader(url, header) {
	return new Promise(function(resolve, reject) {
		var http = new XMLHttpRequest();
	    	http.open('HEAD', url);
    		http.onreadystatechange = function() {
			if (this.readyState !== this.DONE) return;

			if (this.status != 200) {
				reject(this.status);
			} else {

tincho

// make a data uri encoded image from a <video> element using canvas
// (thank you stackoverflow people)
function videoElementToImage(videoElement, width, height) {
    width = width || 360;
    height = height || 240;
    var canvas = document.createElement('canvas');
    canvas.width = width; 
    canvas.height = height;
    var context = canvas.getContext('2d');
    context.drawImage(videoElement, 0, 0, canvas.width, canvas.height);