implement set like get

[gustawdaniel]

In regular computed i can write

computed: {
  message: {
    get () {
      return this.$store.state.obj.message
    },
    set (value) {
      this.$store.commit('updateMessage', value)
    }
  }
}

but there "set" seems to be not implemented.

https://vuex.vuejs.org/guide/forms.html#two-way-computed-property