Sorting, Symbols & Timing

Preview — 3 of 8 questions

What is the output?

javascript

console.log(String.prototype.trimLeft.name === 'trimLeft');
console.log(String.prototype.trimLeft.name === 'trimStart');

Atrue then false

Bfalse then true

Ctrue then true

Dfalse then false

What is the output?

javascript

const numbers = new Set([1, 1, 2, 3, 4]);
console.log(numbers.size);

const letters = new Set('Firefox');
console.log(letters.size);

A5 then 7

B4 then 7

C4 then 6

D5 then 6

What is the output?

javascript

try {
  const sym = new Symbol('id');
  console.log(sym);
} catch (e) {
  console.log(e.constructor.name);
}

ATypeError

BSyntaxError

CSymbol(id)

DReferenceError

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