Challenge 1
Convert the text to a Number.
javascript
Your answer
const age = Number()Press Ctrl⌘Enter to check your answer
Code Completion
8 Challenges
Complete the values, types, and equality expressions
Practice explicit conversion, strict equality, NaN checks, nullish fallback, BigInt, SameValue, and numeric comparison by completing real JavaScript code.
Intermediate
~7 min read
Challenge 2
Convert the empty string to a Boolean.
javascript
Your answer
const ready = Boolean()Press Ctrl⌘Enter to check your answer
Challenge 3
Use strict equality to compare a Number with the same Number.
javascript
Your answer
const same = 42 42;Press Ctrl⌘Enter to check your answer
Challenge 4
Use the explicit NaN test.
javascript
Your answer
const invalid = Number("oops");
const bad = Number.isNaN()Press Ctrl⌘Enter to check your answer
Challenge 5
Choose the nullish fallback operator.
javascript
Your answer
const label = value "Guest";Press Ctrl⌘Enter to check your answer
Challenge 6
Write a BigInt literal.
javascript
Your answer
const total = 9007199254740993;Press Ctrl⌘Enter to check your answer
Challenge 7
Use SameValue semantics for the equality check.
javascript
Your answer
const differentZeroes = Object.is(+0, );Press Ctrl⌘Enter to check your answer
Challenge 8
Force numeric comparison of two numeric strings.
javascript
Your answer
const earlier = Number("10") Number("20");Press Ctrl⌘Enter to check your answer