medium-replace.ts

/* _____________ Your Code Here _____________ */

type Replace<
  S extends string,
  From extends string,
  To extends string,
> = From extends ''
  ? S
  : S extends `${infer L}${From}${infer R}`
  ? `${L}${To}${R}`
  : S;

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

type cases = [
  Expect<Equal<Replace<'foobar', 'bar', 'foo'>, 'foofoo'>>,
  Expect<Equal<Replace<'foobarbar', 'bar', 'foo'>, 'foofoobar'>>,
  Expect<Equal<Replace<'foobarbar', '', 'foo'>, 'foobarbar'>>,
  Expect<Equal<Replace<'foobarbar', 'bar', ''>, 'foobar'>>,
  Expect<Equal<Replace<'foobarbar', 'bra', 'foo'>, 'foobarbar'>>,
  Expect<Equal<Replace<'', '', ''>, ''>>,
];

/* _____________ Further Steps _____________ */
/*
  > Share your solutions: https://tsch.js.org/116/answer
  > View solutions: https://tsch.js.org/116/solutions
  > More Challenges: https://tsch.js.org
*/