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Narrowing safely — Lesson | DistroSource Library

Library / Learning / TypeScript / Module 1: Modelling data

Lesson · Intermediate · 25 min

Narrowing safely

Turning unknown and union values into specific ones with guards the compiler understands.

typescript
lesson

Inside this lesson

You will: Write type guards
You will: Narrow unknown from external data

Sections: 3
Exercise: Yes

The full lesson opens with a membership that covers TypeScript.

Literal types and const

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