code: func compatibleFields(existing FieldDefinition, new FieldDefinition) bool {
  	if existing.Required != new.Required {
  		return false
  	}
  	return existing.Type.Equal(new.Type)
  }
docs: // compatibleFields returns true if the existing and new field are compatible;
  // otherwise false is returned. It does so by comparing all members of the field
  // definition except for the label and description.