What this snippet does
Observer decouples producers from consumers — emitters don't know who's listening, listeners don't know who emits.
Expected output
logged in: Alice first login: Alice logged in: Bob
Why practise typing this
Typing design patterns 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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