fn validate_fields<'a>(
fields: impl Iterator<Item = (&'a str, &'a DataType)>,
descriptor: &MessageDescriptor,
) -> Result<(), FieldEncodeError>
fn validate_fields<'a>(
fields: impl Iterator<Item = (&'a str, &'a DataType)>,
descriptor: &MessageDescriptor,
) -> Result<(), FieldEncodeError>