Union Types in TypeScript: One Value, Two Types #coding #codingtips

A value isn't always just one type. A union type lets a parameter be a number OR a string, and a typeof check tells TypeScript which one it is in each branch. That's narrowing.

In under a minute:
→ Why label("free") fails when the parameter is a number
→ How number | string allows both
→ Why toFixed breaks on a union
→ How typeof narrows the type inside an if
→ What's left after the if: just number

Next up: literal types.

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#typescript #javascript #webdev

Видео Union Types in TypeScript: One Value, Two Types #coding #codingtips канала BiteSized Coding