typescript-katas/6kyu/replace-with-alphabet-position/solution.ts

export function alphabetPosition(text: string): string {
  const alphabet = 'abcdefghijklmnopqrstuvwxyz';
  const indexArray = [...text]
    .map((char) => alphabet.indexOf(char.toLowerCase()))
    .filter((index) => index !== -1)
    .map((index) => index + 1);
  return indexArray.join(' ');
}