Getters with Parameters

While Getters can be accessed directly via $store.getters properties, you may run into situations where you need a bit more control over how the getter works. Parameters provide a way to customize how Getters works. Consider the following store:

import Vue from 'vue'
import Vuex from 'vuex'
Vue.use(Vuex)
export default new Vuex.Store({
  state: {
    books:[
      {type:'nonfiction', title:'Truth about Cats', pages: 200},
      {type:'nonfiction', title:'Truth about Dogs', pages: 100},
      {type:'fiction', title:'The Cat Said Meow', pages: 400},
      {type:'fiction', title:'The Last Dog', pages: 600},
    ]
  },
  getters: {
    fiction(state...