const DOM = (() => {
  const privateData = new WeakMap()
  class DOM{
    constructor(name, count){
      privateData.set(this, {count, name})
    }

    getCount(){
      return privateData.get(this).count
    }
    incCount(num){
      const c = privateData.get(this).count
      privateData.set(this, {
        ...privateData.get(this),
        count:c + num
      })
    }
  }

  return DOM
})();


const dom = new DOM("a" , 5)

console.log(dom.getCount())
dom.incCount(2)

console.log(dom.getCount())


const west = {
  name: "west",
  analogy:"aaa"
}

const getPropValue = (object, text ="") =>
text
.split(".")
.reduce((acc,val) => {
  if(!val || !acc[val]) return acc
  return acc[val]
}, object)

const getName = west => getPropValue(west, "west.name")
const analogy = west => getPropValue(west, "west.analogy")
const age = west => getPropValue(west, "west.age")

const composition = (selectors, transformation) => {
  return input => {
    const dep = selectors.reduce((acc,val) => {
      acc.push(val(input))
      return acc
    }, [])

    return transformation(...dep)
  }
}

const manchester = composition(
  [getName, analogy, age],
  (name, analgoy) => `${name} ${analgoy}`
)(west)

console.log(manchester)