What this snippet does
Optional chaining returns undefined safely, while direct access throws a runtime error if the object is null.
Expected output
undefined TypeError: Cannot read properties of null (reading '0')
Why practise typing this
Typing advanced types code builds muscle memory for the symbols and indentation TypeScript 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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