usage.js

  const audioPlayer = (function () {
    const [state, updateState, watchState] = useState({
      name: 'Ivan',
    })

    watchState({
      name: (name) => {
        console.log('name updated to: ' + name)
      },
    })

    return {
      state,
    }
  })()

useState.js

  const useState = (state = {}) => {
    const watchers = {}

    const update = (fresh) => {
      for (let key in fresh) {
        if (state[key] !== fresh[key]) {
          state[key] = fresh[key]
          watchers[key] && watchers[key].forEach((f) => f(fresh[key]))
        }
      }
    }

    const watch = (watchersObj) => {
      for (let prop in watchersObj) {
        watchers[prop]
          ? watchers[prop].push(watchersObj[prop])
          : (watchers[prop] = [watchersObj[prop]])
      }
    }

    return [state, update, watch]
  }