Array(5) gives you an array with length 5 but no values, hence you can’t iterate over it. Array.apply(null, Array(5)).map(function () {}) gives you an array with length 5 and undefined as values, now it can be iterated over. Array.apply(null, Array(5)).map(function (x, i) { return i; }) gives you an array with length 5 and values … Read more
There is no difference for a simple object without methods as in your example. However, there is a big difference when you start adding methods to your object. Literal way: function Obj( prop ) { return { p : prop, sayHello : function(){ alert(this.p); }, }; } Prototype way: function Obj( prop ) { this.p … Read more
My view is to always use ++ and — by themselves on a single line, as in: i++; array[i] = foo; instead of array[++i] = foo; Anything beyond that can be confusing to some programmers and is just not worth it in my view. For loops are an exception, as the use of the increment … Read more
Update for ES6 modules Inside native ECMAScript modules (with import and export statements) and ES6 classes, strict mode is always enabled and cannot be disabled. Original answer This article about Javascript Strict Mode might interest you: John Resig – ECMAScript 5 Strict Mode, JSON, and More To quote some interesting parts: Strict Mode is a … Read more