21104 - FindAll

[DevilTea]

// your answers
type FirstCharOf<S extends string> = S extends `${infer C}${any}` ? C : ''
type LengthOf<S extends string, Result extends 0[] = []> = S extends `${any}${infer Rest}`
  ? LengthOf<Rest, [0, ...Result]>
  : Result['length']
type FindAll<T extends string, P extends string, Result extends number[] = [], Scanned extends string = ''> = P extends ''
  ? []
  : T extends `${Scanned}${infer Head}${P}${infer Tail}`
    ? FindAll<T, P, [...Result, LengthOf<`${Scanned}${Head}`>], `${Scanned}${Head}${FirstCharOf<P>}`>
    : Result