JavaScript Sample

this works as expected [97,98].map(function(x){String.fromCharCode(x)}) // [ 'a', 'b… Read more Weird Output Of [97,98].map(string.fromcharcode)

Why can't I assign new properties to non-frozen object, which has frozen prototype: Working wit… Read more Assign New Property To Empty Object Which Has Frozen Prototype

What scope does the strict mode pragma have in ECMAScript5? 'use strict'; I'd like to … Read more In Ecmascript5, What's The Scope Of "use Strict"?

I'm reading up a bit on using Strict Mode for JavaScript and it seems that, generally speaking,… Read more Does Javascript (ecmascript5) Strict Mode Offer Significant Performance Advantages To Merit Widespread Use?

In ECMAScript specification there is notion of 'realms' introduced: Before it is evaluated… Read more How To Understand Js Realms

I'm trying to use defineProperty to made attributes not appear in for...in cycle, but it doesn&… Read more Javascript Defineproperty To Make An Attribute Non Enumerable

For background, please refer to this question: Access deep object member of embeded JSON The soluti… Read more Getpathvalue() Function For Deep Objects With Arrays And With Packed Json

Certain ECMAScript environments permit switiching into a special mode by means of a Directive Prolo… Read more Ecmascript Multiple Prologue Directives

According to the spec (Annex C), strict-mode code can't do pretty much anything that might assi… Read more Why Does Ecmascript 5 Strict Mode Go To Such Great Lengths To Restrict The Identifier `eval`

I think it is an old Javascript behavior (Crockford said it is a design error) that inside a functi… Read more For Javascript, What Prevents Modern Implementation Not To Treat Arguments As A Real Array?

I have an object fetched from 3rd party API as shown below: { name:'Luke Skywalker', … Read more Access The Value Of Symbol(id) Property On An Object

I'm currently developing a 2D graphic library in JavaScript, and now I'm sticking with the … Read more How To Transform The Image Pattern In Javascript Canvas Fillingstyle?

I have an complex object and based on an input array I need to modify properties inside of this com… Read more Manipulating A Complex Object Based On An Input Array

I'm using ES5. I'm learning JavaScript. I did this modal, but I want to re-factor the code … Read more Functional JavaScript Programming - Making A Modal, A Popup, And Refactoring It

I am using the following code for a slider with Siema: https://codepen.io/pawelgrzybek/pen/boQQWy W… Read more Javascript - Extend An ES6 Class In ES5