- From: Henry S. Thompson <ht@inf.ed.ac.uk>
- Date: Thu, 22 Jan 2004 13:56:08 +0000
- To: holstege@mathling.com
- Cc: "Dare Obasanjo" <dareo@microsoft.com>, <xmlschema-dev@w3.org>, www-xml-schema-comments@w3.org
The REC says in clause 1.5 of Schema Component Constraint: Derivation Valid (Extension) [1]: Note: This requirement ensures that nothing removed by a restriction is subsequently added back by an extension. That (rather than clause 1.2 as I think Mary was suggesting) is where the REC tries to answer "no" to the question of "whether an attribute [or element] removed by restriction could be added back in an extension." However the constraint itself, in my view, fails to achieve this, so processors which allow it are not broken. I think we should fix this one way or another -- what do you think is best: 1) No constraint on re-introduction; 2) No re-introduction of any kind (apparent intention of current REC); 3) Re-introduction of unchanged originals only (what the current REC actually says)? ht [1] http://www.w3.org/TR/xmlschema-1/#cos-ct-extends -- Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh Half-time member of W3C Team 2 Buccleuch Place, Edinburgh EH8 9LW, SCOTLAND -- (44) 131 650-4440 Fax: (44) 131 650-4587, e-mail: ht@inf.ed.ac.uk URL: http://www.ltg.ed.ac.uk/~ht/ [mail really from me _always_ has this .sig -- mail without it is forged spam]
Received on Thursday, 22 January 2004 09:00:55 UTC