What this snippet does
typeof null returns 'object' which is a JavaScript bug kept for backwards compatibility — always use === null instead.
Expected output
object true true false
Why practise typing this
Typing types code builds muscle memory for the symbols and indentation JavaScript uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.
More JavaScript practice
- typeof operatorTypes · beginner
- implicit coercionTypes · beginner
- loose equalityTypes · intermediate
- explicit conversionTypes · intermediate
- let vs constVariables · beginner
- const configVariables · beginner