Tricky Outputs

Preview — 3 of 10 questions

What is the output?

javascript

for (var i = 0; i < 3; i++) {
  setTimeout(() => console.log(i), 0);
}

A0 1 2

B0 0 0

Cundefined undefined undefined

D3 3 3

What is the output?

javascript

function makeCounter() {
  let count = 0;
  return function () {
    count++;
    return count;
  };
}

const counter = makeCounter();
console.log(counter());
console.log(counter());
console.log(counter());

A1 2 3

B1 1 1

C0 1 2

D0 0 0

What is the output?

javascript

const obj = {
  name: "Alice",
  greet: function () {
    setTimeout(function () {
      console.log(this.name);
    }, 0);
  },
};
obj.greet();

Aundefined

B"Alice"

CReferenceError

Dnull

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