What this snippet does
Number.isNaN is more reliable than global isNaN — the global one coerces its argument first, causing surprises.
Expected output
true false false true true false true false
Why practise typing this
Typing numbers 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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