Quizzes » The non-values `undefined` and `null`

1. Accessing properties

const result = true.unknownProperty;

What happens?

assert.equal(result, undefined)

TypeError

SyntaxError

const result = null.unknownProperty;

What happens?

assert.equal(result, undefined)

TypeError

SyntaxError

Given the following JavaScript code.

let foo;
function bar() {}
const baz = (x) => x;

Which of these expressions evaluates to undefined? The remaining ones evaluate to null.

assert.equal(foo, undefined)

assert.equal(bar(), undefined)

assert.equal(baz(), undefined)

assert.equal(/^#/.exec('Z'), undefined)

Correct answers: 0 out of 0