Closed
Description
Duplicate option names are a data model error, while duplicate attribute names are allowed.
This makes the implementation a little more complicated, as the code is less uniform when it comes to parsing options vs. attributes.
I know that since attributes are reserved for future use, it might be a bit weird to emit errors related to them. Still, unless there's a use case for multiple attributes with the same name, maybe it's worth specifying that attribute names, like option names, must be unique?