Javascript reduce function and dynamic keys in es6 format

reduce.md

Objects can be created with computed keys, so es6.ruanyifeng.com is not enough.

const obj = {
  [variable]: value,
}

Reduce, the simplest way to accummulate datas. reduce set first item as initial value default.

const total = ['age', 'name', 'favourite'].map(key => dataLists.reduce((sum, data) => ({
  [key]: +sum[key] + parseFloat(data[key])
})))

from code above, if you want to convert a string to number, just place an + plus operator before the string

Above code can be refactored, expense too much

const keys = ['age', 'name', 'favourite']
dataList.reduce((sum, data) => {
  return keys.reduce((count, key) => {
    count[key] = +sum[key] + parseFloat(data[key])
    return count
  }, {})
})