parameter entity references in contentspec's

Hello,

In section 3.2.1 of the XML Standard on Element Content, the validity
constraint
labeled "Proper Group/PE Nesting" contains a paragraph on interoperability:

    "For interoperability, if a parameter-entity reference appears in a
choice, seq, or Mixed construct,
     its replacement text should not be empty, and neither the first nor
last non-blank character of the
     replacement text should be a connector (| or ,)."

Should you include a phrase that indicates that, in these contexts, the
replacement text should also
not consist solely of white-space?   If such a parameter entity did consist
solely of whitespace, then
a construct like the following:

            ( %stuff | another-type)

would parse as

            (       | another-type)

yielding a syntax error, if there existed a preceding parameter entity
declaration as follows:

    <!ENTITY % stuff "    ">


Sincerely,

Gregory Zelesnik
Senior Systems Engineer
Evolutionary Systems, Incorporated.

Received on Thursday, 12 November 1998 10:38:27 UTC