code: func (s *UnionSchema) Validate(v reflect.Value) bool {
  	v = dereference(v)
  	for i := range s.Types {
  		if t := s.Types[i]; t.Validate(v) {
  			return true
  		}
  	}
  
  	return false
  }
docs: // Validate checks whether the given value is writeable to this schema.