title: Vue js with vuex computed properties with v-for and v-model
body: <p>I need to use v-for with v-model. I read the <a href="http://vuex.vuejs.org/en/forms.html" rel="noreferrer">docs</a> and there is no example of how to use it with v-for without performing mutation outside the mutation handler. </p>
  
  <p>How can I use v-model inside v-for without mutating the property directly?</p>
  
  <pre><code>  &lt;div v-for="product in products"&gt;
       &lt;select @change="addItem(product)" v-model="product.quantity"&gt;
          &lt;option value=""&gt;0&lt;/option&gt;
          &lt;option v-for="n in 10"&gt;{{n}}&lt;/option&gt;
        &lt;/select&gt;
    &lt;/div&gt;
  
   // component
  
    methods : {
      ...mapMutations({
        addToCart: ADD_TO_CART
      })
    },
  </code></pre>