reference to parameter entity in token separator in internal [VE][413]

Hi, what's the meaning of the warning "reference to parameter
entity in token separator in internal subset" (= [VE][413]) ?

The (homebrewn) DTD says (excerpt):

<!ENTITY % types  "language*, extlang*, script*, region*, variant*">
<!ENTITY % legacy "grandfathered*, redundant*">
<!ELEMENT LanguageSubtagRegistry (%types;, %legacy;)>

The validator emits warnings for %types; and %legacy; (and 13
similar warnings for other parameter entities).  

In the XML spec. I found that brackets in parameter entities
must be properly nested, no issue for my case (and that would
be an error).  It also recommends that parameter entities
don't start or end with separators (comma for a sequence, or
vertical bar for a choice), also no issue for my case.

I tried to add spaces as in ( %types; , %legacy; ), but that
didn't kill the PE warnings.

When I substitute the PEs I get as expected no warning, but the
DTD is less "human readable" (as far as humans read DTDs :-)

Tested document: <>

Received on Friday, 22 September 2006 22:18:33 UTC