Vue JS - Using both Vue 2 and Vue 3 in a project

Question

I'm trying to utilise a function defined in a JS class component. In order to use the said function in composition api I would the following:

setup(props) {
  const {errorMessages, handleInput, setFieldData} = Validator.register(props); // function to use

  return {
     errorMessages,
     handleInput,
     input
  }
}

How can I do the same exact thing but with a syntax that vue 2 is familiar with?

Answer 1

That's roughly the equivalent of:

data() {
  const {errorMessages, handleInput, setFieldData} = Validator.register(this._props);
  
  return {
    errorMessages,
    handleInput,
    input           // undefined btw
  }
}

You can alternatively install the composition api in Vue 2:

npm install @vue/composition-api

import Vue from 'vue'
import VueCompositionAPI from '@vue/composition-api'

Vue.use(VueCompositionAPI)