In App, you should wrap the :refs in :schena , like [:schema [:ref :lit]] so that they are not inlined in the :cat.

Thanks, that works. I think I understand what you mean by “inlined by the :cat” but I am surprised that :ref must be wrapped. I thought only seqex schemas (`:cat` , :*, :alt, etc) had to be wrapped to prevent inlining. I am probably not understanding something about seqex in general. I’ll keep reading. Thanks again!