What this snippet does
??= only assigns when the value is null or undefined — 0 and false are kept as-is, unlike ||= which would overwrite them.
Expected output
0 3 false
Why practise typing this
Typing modern js 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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