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← JavaScript
#1 most askedVery commonMediumScope & closures

What is a closure?

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Explain what a closure is, and give a practical example of when you'd use one.

🔮 Predict the output

function makeCounter() {
  let count = 0;
  return () => ++count;
}
const a = makeCounter();
const b = makeCounter();
a();
a();
console.log(a(), b());

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