What this snippet does
When multiple arguments share a generic but are passed different types, TypeScript infers a union or the base type.
Expected output
[ 1, 'a' ]
Why practise typing this
Typing advanced generics 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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