Re: XSchema: unparsed entities

John Cowan (cowan@locke.ccil.org)
Fri, 24 Jul 1998 16:38:47 -0400


Ron Bourret scripsit:

> One other difference I'd like to point out is that, with the exception of the
> "escape character" entities (lt, gt, amp, quot, and apos), I don't think you can
> construct an XML file with parsed entities that you cannot construct without
> them.

Actually, they too can be "compiled out" by clever use of character
references: see the table in clause 4.6 of XML 1.0.

> This is not true of unparsed entities. Not only would an UnparsedEntity
> element rectify this problem, it would also solve the validation problem pointed
> out by John Cowan with respect to ENTITY attributes: we can't validate their
> value without unparsed entity declarations.

Okay, I'm convinced. (Note also that SAX supports them.)

How about:

<!ELEMENT UnparsedEntityDef>
<!ATTLIST UnparsedEntityDef
Name CDATA #REQUIRED
SystemLiteral CDATA #REQUIRED
PubidLiteral CDATA #IMPLIED
Notation CDATA #REQUIRED>

-- 
John Cowan	http://www.ccil.org/~cowan		cowan@ccil.org
	You tollerday donsk?  N.  You tolkatiff scowegian?  Nn.
	You spigotty anglease?  Nnn.  You phonio saxo?  Nnnn.
		Clear all so!  'Tis a Jute.... (Finnegans Wake 16.5)