What this snippet does
Well-known Symbols like Symbol.iterator and Symbol.toStringTag let you hook into language-level behaviors on your own classes.
Expected output
[ 1, 2, 3 ] [object Collection]
Why practise typing this
Typing symbols 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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