“Szybsza tablica filtru w JavaScript” Kod odpowiedzi

Szybsza tablica filtru w JavaScript

const filterArray = (array, identify) => {
  const matches = {};
  return array.filter(item => {
    const identity = identify(item);
    const isExists = identity in matches;
    if (!isExists) {
      matches[identity] = true;
      return true
    }
    return false;
  });
};