What this snippet does
Explicitly returning null in a union type forces callers to handle the missing value case.
Expected output
null
Why practise typing this
Typing basic 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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- Pushing a wrong type to a typed arrayBasic Types · beginner