[Vue] Options API => Composition API

Options API => Composition API

Options API                    |        Composition API
data() {...}                   |        ref(), reactive()
methods: {doSmth() {...}}      |        function doSmth() {...}
computed: {val() {...}}        |        const val = computed()
watch: {...}                   |        watch(dep, (val, oldV) => {})
provide: {...} / inject: []    |        provide(key, val), inject(key)