KKrisu

function getHash (v) {
    return v.x+'-'+v.y+'-'+v.z;
}

function solve(input) {
    
    var l = input.length,
        map = {};
    
    while(l--) {

KKrisu

function getHash (v) {
    
    return v.x+'_'+v.y+'_'+v.z;
    
}

function solve(input) {
    
    var l = input.length,
        map = {},

KKrisu

// multiline conditional operator (source: three.js)
var newTime = self.performance !== undefined && self.performance.now !== undefined
    ? self.performance.now()
    : Date.now();

KKrisu

We couldn’t find that file to show.

KKrisu

<!-- To avoid spaces between inline-block elements and still have enter between them in the code.  -->
<ul>
  <li><!--
  --></li>
  <li><!--
  --></li>
</ul>

KKrisu

input: var a = [2, 3, 5]
Task: we want to fill array with undefineds to 6th element.
output: [2, 3, 5, undefined, undefined, undefined]

ES5 solutions:

1. a.length = 6 result: [2, 3, 5, undefined x 3]
   Problem: this array has sparse elements (holes) on elements 3-5. We can iterate through it like: for (i = a.length ; i-- ;) {}, but when we iterate like: a.forEach(callback) it only goes through iterable values.

KKrisu

let / const declarations do hoist, but they throw errors when accessed before being initialized (instead of returning undefined as var would)

let x = 'outer scope';
console.log(x); // => outer scope

(function() {

  console.log(x); // => ReferenceError (let is hoisted, but doesn't allow accessing)
  
  console.log(y); // => undefined (var is hoisted and allows accessing)

KKrisu

// FUNCTIONS

// use on babeljs.io/repl


function declaration() {
  console.log('declaration');
}

var expression = function() {

KKrisu

// # Arrays

// var a = ['a', 'b', 'c'];

// var i = a[0];
// var j = a[1];
// var k = a[2];

// var [i, j, k] = a;
// var [i, j, k] = ['a', 'b', 'c'];

KKrisu

// var text = `something`;

// var template = '' +
//   '<div>' +
//     '<input>' +
//   '</div>';
  
// console.log(template);

// var template2 = `