00043-easy-exclude.ts

/*
  43 - Exclude
  -------
  by Zheeeng (@zheeeng) #easy #built-in
  
  ### Question
  
  Implement the built-in Exclude<T, U>
  > Exclude from T those types that are assignable to U
  
  > View on GitHub: https://tsch.js.org/43
*/

/* _____________ Your Code Here _____________ */

type MyExclude<T, U> = T extends U ? never : T; 

/* _____________ Test Cases _____________ */
import type { Equal, Expect } from "@type-challenges/utils";

type cases = [
  Expect<Equal<MyExclude<"a" | "b" | "c", "a">, Exclude<"a" | "b" | "c", "a">>>,
  Expect<
    Equal<
      MyExclude<"a" | "b" | "c", "a" | "b">,
      Exclude<"a" | "b" | "c", "a" | "b">
    >
  >,
  Expect<
    Equal<
      MyExclude<string | number | (() => void), Function>,
      Exclude<string | number | (() => void), Function>
    >
  >
];


type a = MyExclude<'a' | 'b' | 'c', 'a'>

/* _____________ Further Steps _____________ */
/*
  > Share your solutions: https://tsch.js.org/43/answer
  > View solutions: https://tsch.js.org/43/solutions
  > More Challenges: https://tsch.js.org
*/