SetIntersection<A, B> (same as Extract)

[nmsn]

Set intersection of given union types A and B

import { SetIntersection } from 'utility-types';

// Expect: "2" | "3"
type ResultSet = SetIntersection<'1' | '2' | '3', '2' | '3' | '4'>;
// Expect: () => void
type ResultSetMixed = SetIntersection<string | number | (() => void), Function>;

[nmsn]

/**
 * SetIntersection (same as Extract)
 * @desc Set intersection of given union types `A` and `B`
 * @example
 *   // Expect: "2" | "3"
 *   SetIntersection<'1' | '2' | '3', '2' | '3' | '4'>;
 *
 *   // Expect: () => void
 *   SetIntersection<string | number | (() => void), Function>;
 */
export type SetIntersection<A, B> = A extends B ? A : never;