UnionToIntersection<Union>

UnionToIntersection<Union> = Union extends unknown ? (distributedUnion: Union) => void : never extends (mergedIntersection: infer Intersection) => void ? Intersection & Union : never

Defined in: packages/react-querybuilder/src/types/type-fest/union-to-intersection.ts:46

Convert a union type to an intersection type using distributive conditional types.

Inspired by this Stack Overflow answer.

Type Parameters

Type Parameter
Union

Examples

import type {UnionToIntersection} from 'type-fest';

type Union = {the(): void} | {great(arg: string): void} | {escape: boolean};

type Intersection = UnionToIntersection<Union>;
//=> {the(): void; great(arg: string): void; escape: boolean};

A more applicable example which could make its way into your library code follows.

import type {UnionToIntersection} from 'type-fest';

class CommandOne {
	commands: {
		a1: () => undefined,
		b1: () => undefined,
	}
}

class CommandTwo {
	commands: {
		a2: (argA: string) => undefined,
		b2: (argB: string) => undefined,
	}
}

const union = [new CommandOne(), new CommandTwo()].map(instance => instance.commands);
type Union = typeof union;
//=> {a1(): void; b1(): void} | {a2(argA: string): void; b2(argB: string): void}

type Intersection = UnionToIntersection<Union>;
//=> {a1(): void; b1(): void; a2(argA: string): void; b2(argB: string): void}

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caution

API documentation is generated from the latest commit on the main branch. It may be somewhat inconsistent with official releases of React Query Builder.