const pluckDeep = key => obj => key.split('.').reduce((accum, key) => accum[key], obj)

​

const compose = (...fns) => res => fns.reduce((accum, next) => next(accum), res)

​

const unfold = (f, seed) => {

  const go = (f, seed, acc) => {

    const res = f(seed)

    return res ? go(f, res[1], acc.concat([res[0]])) : acc

  }

  return go(f, seed, [])

}