What this snippet does
once is useful for initialization logic that should only run once — subsequent calls return the cached result silently.
Expected output
initializing...
{ ready: true }
{ ready: true }
{ ready: true }Why practise typing this
Typing functions 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
- function hoistingFunctions · beginner
- function expressionsFunctions · beginner
- arrow functionsFunctions · beginner
- arrow thisFunctions · intermediate
- default paramsFunctions · beginner
- rest paramsFunctions · beginner