vm_instance.js

  //pass vm (name is up to you) to data function in order get access to the present vue instance in nested objects
  data: vm => ({
    valid: true,
    name: '',
    email: '',
    password: '',
    confirmPassword: '',
    // in a non nested object, 'this' is enough to access the properties in the data function
    /*     matchPassword2() {
      return this.password === this.confirmPassword || 'Password do not match.'
    }, */