word$.js

function isChar(key) {
  return characters.includes(key);
}

function isSpace(key) {
  return key === 'space'
}

const keyup$ = Observable.fromEvent(promptInput, 'keyup')
  .map(keycode)

const char$ = keyup$.filter(isChar)
const space$ = keyup$.filter(isSpace)

export const word$ = char$
  .buffer(() => space$)
  .map(listOfChar => listOfChar.join(''))