types.branded.md

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Branded type

Create a Branded type with a given BrandName.

Signature:

type Branded<T, BrandName extends string> = T extends WithBrands<infer Base, infer ExistingBrands>
    ? WithBrands<Base, BrandName | ExistingBrands>
    : WithBrands<T, BrandName>;

References: WithBrands

Remarks

In order for TypeScript to consider a type separate from another type, we need to brand it. When a type is branded TypeScript will manage correct assignability during TypeScript-compilation, e.g. int is assignable to number, but number is not assignable to int.