What this snippet does
TypeScript prevents accessing properties on nullable types unless you explicitly check for null first.
Expected output
Compile Error: Object is possibly 'null'.
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.
More TypeScript practice
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- Falling back to a default with ??Advanced Types · beginner