What this snippet does
yield* delegates to another iterable — combining it with Symbol.iterator makes recursive tree traversal elegant.
Expected output
[ 1, 2, 4, 5, 3, 6 ]
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.
More JavaScript practice
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