simpleClosure.js

const init = function(type) {
  let id = 0;
  return (name, props=null) => {
    id +=1;
    return {
      id,
      type,
      name,
      ...props
    }
  }
}

const createUser = init('user')
const createBook = init('book')

const dave = createUser('Dave')
const book = createBook('Moby Dick', { author: createUser('Herman') })

console.dir(dave)
console.dir(book)