Scope and closures

A closure is created when an inner function remembers variables from its outer lexical environment, even after the outer function finishes executing.

Worked example

How it reads

let count = 0 defines a private counter variable
return () => { ... } maintains lookup access to the count variable

Cloud tip: Closures allow you to create private state variables in JavaScript.

index.js

JAVASCRIPT

real JavaScript, runs in your browser

Console

Run your code to see its output here.

YOUR TURN

Write makeCounter() that returns a function adding 1 to a private count each call. Call it three times and log the last result: 3.

Press Run to check your work.

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