34 lines
848 B
TypeScript
Executable file
34 lines
848 B
TypeScript
Executable file
import {Except} from './except';
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/**
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Create a type that requires at least one of the given keys. The remaining keys are kept as is.
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@example
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```
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import {RequireAtLeastOne} from 'type-fest';
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type Responder = {
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text?: () => string;
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json?: () => string;
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secure?: boolean;
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};
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const responder: RequireAtLeastOne<Responder, 'text' | 'json'> = {
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json: () => '{"message": "ok"}',
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secure: true
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};
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```
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*/
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export type RequireAtLeastOne<
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ObjectType,
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KeysType extends keyof ObjectType = keyof ObjectType
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> = {
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// For each `Key` in `KeysType` make a mapped type:
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[Key in KeysType]-?: Required<Pick<ObjectType, Key>> & // 1. Make `Key`'s type required
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// 2. Make all other keys in `KeysType` optional
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Partial<Pick<ObjectType, Exclude<KeysType, Key>>>;
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}[KeysType] &
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// 3. Add the remaining keys not in `KeysType`
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Except<ObjectType, KeysType>;
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