JavaScript

nullish defaults in JavaScript

JavaScriptOperatorsnullish coalescingbeginner

What this snippet does

?? lets 0 and false be valid config values while still providing fallbacks for truly missing options.

Expected output

port=8080 timeout=5000 debug=false
port=0 timeout=5000 debug=false
port=3000 timeout=5000 debug=false

Why practise typing this

Typing operators 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.

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