Functions & Scope — Series 3

Preview — 3 of 10 questions

What is logged?

javascript

const fns = [];
for (var i = 0; i < 3; i++) {
  fns.push(((n) => () => n)(i));
}
console.log(fns.map((f) => f()).join(' '));

A3 3 3

B0 1 2

Cundefined undefined undefined

D2 2 2

What is logged?

javascript

const mod = (function () {
  let secret = 'hidden';
  return { reveal: () => secret };
})();

console.log(mod.reveal());
console.log(typeof secret);

A"hidden", "string"

Bundefined, "undefined"

CReferenceError: secret is not defined

D"hidden", "undefined"

What is logged?

javascript

function outer() {
  const inner = () => arguments.length;
  return inner(1, 2, 3);
}

console.log(outer('a', 'b'));

DTypeError: arguments is not defined

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