What this snippet does
Object.hasOwn is safer than hasOwnProperty because it works on null-prototype objects and can't be shadowed by a property.
Expected output
true false true true
Why practise typing this
Typing modern js 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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