gistfile1.txt

    // imperative
    const isSelected = playlist => {
      const slides = getOr([], 'config.slides', playlist);
      return some(matchesProperty('key', item.key), slides);
    };
    // functional
    const isSelected = compose([
      partial(some, matchesProperty('key', item.key)),
      partial(getOr, [], 'config.slides'),
    ]);