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JavaScript Introducing ES2015 ES2015 Basics Let and Const

Samuel Kleos
Samuel Kleos
Front End Web Development Techdegree Student 12,719 Points

More detail . . . 🧐 Where is the function scope? Declaration or Execution?

I don't understand where the accessible scope of doLoop(x) lies.

Does the doLoop(x) functions' accessible scope depend on where it's called / executed? i.e. inside the for loop?

Or is the doLoop(x) function have access to variables that are in the scope of where it's declared? i.e. in the top level of the initLoop() function?

From what I understand, the function will have access to variables and other functions within itself and outside itself in the scope of where it's declared.

'use strict';

(function initLoop() {
  function doLoop(x) {
    console.log('loop:', x);

  for (var i = 0; i < 10; i++) {
    doLoop(i + 1);

1 Answer

Steven Parker
Steven Parker
229,788 Points

If by "outside itself" you are including all wider scopes (such as global scope), then it sounds like you have it. :+1:

You might want to try a few experiments to prove to yourself that variables in the execution scope will show up as "undefined".