What this snippet does
Implementing Symbol.iterator lets your custom objects work in for...of, spread, destructuring — the full iteration protocol.
Expected output
[ 1, 2, 3, 4, 5 ] 1 2 3 4 5
Why practise typing this
Typing iterators 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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