store
│ index.js
│ 
├─feeds
│   actions.js
│   getters.js
│   index.js
│   mutation-type.js
│   mutations.js
│   state.js
│   
└─movies
    actions.js
    getters.js
    index.js
    mutation-type.js
    mutations.js
    state.js

import Vue from 'vue';
import Vuex from 'vuex';
import feeds from './feeds';
import movies from './movies';

Vue.use(Vuex);

export default new Vuex.Store({
 modules: {
  feeds,
  movies
 },
});

import state from './state';
import mutations from './mutations';
import actions from './actions';
import getters from './getters';

export default {
    namespaced: true, //多出的一行
    state,
    mutations,
    actions,
    getters
};    

import { mapState, mapMutations } from "vuex";

export default {
computed:{
  ...mapStated('模块名（嵌套层级要写清楚）',{ //比如'movies/hotMovies
    a:state=>state.a,
    b:state=>state.b
  })
},

import { mapActions } from 'vuex'
methods:{
  ...mapActions('模块名（嵌套层级要写清楚）',[ //比如'movies/getHotMovies
    'foo',
    'bar'
  ])
}