What this snippet does
Symbol-keyed properties don't show in for...in, Object.keys, or JSON.stringify — useful for attaching private metadata.
Expected output
42
[ 'name' ]
{"name":"Alice"}
[ Symbol(id), Symbol(secret) ]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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