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Neo42/mapped-types-&-modifiers.ts

Last active January 8, 2022 06:47
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Mapped types are the for...in loop for types.
Raw
mapped-types-&-modifiers.ts
interface Fruit {
readonly name?: string
readonly color?: string
readonly sweetness?: number
}
type Properties<Type> = keyof Type
type Values<Type> = Type[Properties<Type>]
type FruitProperties = Properties<Fruit>
type FruitValues = Values<Fruit>
type ReadonlyObject<Type> = {
-readonly [property in Properties<Type>]-?: Type[property]
}
type ReadonlyFruit = ReadonlyObject<Fruit>
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