SOURCE

var app = new Vue({
    el: '#app',

    data() {
        return {
            args: [],
            formEdit: {}
        }
    },
    watch: {
        'formEditComputed': {
            handler: function(newVal, oldVal) {
                console.log(oldVal);
                console.log(newVal);
            }
        }
    },
    computed: {
        formEditComputed() {
            return {
                answer_rule: this.formEdit.answer_rule
            }
        }
    },
    methods: {
        click1(row) {
            this.formEdit = row;
        }
    },
    mounted() {
        axios.get('http://httpbin.org/get?answer_rule=2').then(response => {
            this.args = [response.data.args];
        }).catch(function (error) {
            console.log(error);
        });
    }
});

<div id="app">
<div v-for="(r,k) in args" :key="k">
    <button @click="click1(r)">{{r}}</button>
</div>
	{{formEditComputed.answer_rule}}
</div>