new_modules.ts

import {Module, VuexModule, Mutation, Action} from 'vuex-module-decorators' 

@Module
export default class Counter2 extends VuexModule {
  count = 0

  @Mutation increment(delta: number) {this.count+=delta}
  @Mutation decrement(delta: number) {this.count-=delta}

  // action 'incr' commits mutation 'increment' when done with return value as payload
  @Action({commit: 'increment'}) incr() {return 5}
  // action 'decr' commits mutation 'decrement' when done with return value as payload
  @Action({commit: 'decrement'}) decr() {return 5}
}