What this snippet does
sort, reverse, and splice mutate the original array — always spread or slice first when you want a non-destructive sort.
Expected output
original mutated: [ 1, 1, 3, 4, 5, 9 ] original intact: [ 3, 1, 4, 1, 5, 9 ]
Why practise typing this
Typing arrays 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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