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TypeScript Typing Practice

Practice TypeScript annotations, interfaces, unions, generics, utility types, and typed async code.

TypeScript / Type Annotations / Type Annotations

Primitive annotations

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primitive-annotations.tsStart typing to begin
30

Start typing to begin

Start typing to begin const userId: number = 42; const isActive: boolean = true;
TypeScript0 CPM0 WPM0 errors00:000 / 58