SOURCE

const store = new Vuex.Store({
  getters: {
    someOtherGetter: state => 'ROOT'
  },
  actions: {
    someOtherAction() {
      console.log('ROOT_ACTION');
    }
  },
  modules: {
    moduleA: {
      namespaced: true,
      getters: {
        someGetter(state,getters,rootState,rootGetters) {
          return getters.someOtherGetter; // INSIDE
          // return rootGetters.someOtherGetter; // ROOT
        },
        someOtherGetter: state => "INSIDE"
      },
      actions: {
        someAction({ dispatch, getters, rootGetters }) {
          console.log(getters.someOtherGetter);//INSIDE
            console.log(rootGetters.someOtherGetter);//ROOT
          dispatch('someOtherAction');//INSIDE_ACTION
          dispatch('someOtherAction', null, {root: true});//ROOT_ACTION
        },
        someOtherAction() {
          console.log('INSIDE_ACTION');
        }
      }
    }
  }
});
console.log(store.getters['moduleA/someGetter']);
store.dispatch('moduleA/someAction');

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