What this snippet does
Lazy evaluation defers expensive computation until the value is needed — and caches it so the cost is paid only once.
Expected output
computing... 499999500000 499999500000 499999500000
Why practise typing this
Typing performance 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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