- From: Steven J. DeRose <sjd@ebt.com>
- Date: Fri, 01 Nov 1996 10:42:11 -0500
- To: DAVEP@acm.org, W3C-SGML-WG@w3.org
>All this trickery does indeed get very fragile. There is a proposal >that will probably be considered at the combined ISO/ANSI meeting >the week before SGML '96 that proposes a neat solution using >different closes as well as opens for start- and end-tags. Among >other things, it requires that EMPTY or CONREFed elements use the >STAGO and the ETAGC for their "start"-tag. For example, if STAGC >were "/>" and ETAGC were ">", then "<x/>..<y>..</x> would be an >x element with content that included an empty y element. A good beginning (as WG8 members know, I have often requested that the overloaded delimiter roles be divided). So I would strongly support a revision along that line. However, if you only make empties use STAGO+ETAGC you can't distinguish ETAGC from empty-tag-C, which is essential. EMPTY should have its *own* delimiters, or you pointlessly rule out perfectly fine syntaxes, including the one we just approved! That is, the delimiters should be broken down to something like this, which imposes no backward-compatibility limitation, but opens the road forward completely rather than partially: STAGO STAGC for start-tags ETAGO ETAGC for end-tags MTAGO MTAGC for EMPTY/conref/etc. Likewise, the "I can't use curly quotes" problem should become a non-issue: LITO LITC LITAO LITAC And COMO COMC The language-bias issues from punning on "+" meaning "repetition" and "+" means "addition", etc. imply the need for PLUS to be divided into INCLUSION vs REQ; and MINUS to EXCLUSION vs. CAN-OMIT-TAG; and so on. Basically, any time a delimiter appears in more than one 8879 production, there's a limitation on the range of definable syntaxes, and thus a potential problem requiring review. S
Received on Friday, 1 November 1996 10:45:31 UTC