37 lines
857 B
TypeScript
37 lines
857 B
TypeScript
/**
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Given a [literal type](https://www.typescriptlang.org/docs/handbook/2/everyday-types.html#literal-types) return the {@link Primitive | primitive type} it belongs to, or `never` if it's not a primitive.
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Use-case: Working with generic types that may be literal types.
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@example
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```
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import type {LiteralToPrimitive} from 'type-fest';
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// No overloads needed to get the correct return type
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function plus<T extends number | bigint | string>(x: T, y: T): LiteralToPrimitive<T> {
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return x + (y as any);
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}
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plus('a', 'b'); // string
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plus(1, 2); // number
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plus(1n, 2n); // bigint
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```
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@category Type
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*/
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export type LiteralToPrimitive<T> = T extends number
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? number
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: T extends bigint
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? bigint
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: T extends string
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? string
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: T extends boolean
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? boolean
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: T extends symbol
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? symbol
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: T extends null
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? null
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: T extends undefined
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? undefined
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: never;
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