- From: C. M. Sperberg-McQueen <cmsmcq@blackmesatech.com>
- Date: Wed, 17 Oct 2012 20:51:36 -0600
- To: George Cristian Bina <george@oxygenxml.com>
- Cc: "C. M. Sperberg-McQueen" <cmsmcq@blackmesatech.com>, "G. Ken Holman" <gkholman@CraneSoftwrights.com>, xmlschema-dev@w3.org
On Oct 17, 2012, at 8:39 AM, George Cristian Bina wrote: > Expression every possible permutation does not generally work as you will get a lot of errors from the unique particle attribution rule that will not allow you to say for example > (a, b, x) | (a, b, y) > forcing you to write > (a, b, (x | y)) > instead. > > However, for a complex model getting the right expression is not easy and sometimes it may be impossible. I agree that it is often difficult, and the result is almost never easy to read and understand. But I do not believe it is ever impossible. There is a definable class of regular languages for which deterministic content models are impossible, and the problem of interleaving a number of elements with different occurrence constraints does not look at first glance as if it had the required properties. (But I have not attempted a formal proof of this proposition and I may be wrong.) -- **************************************************************** * C. M. Sperberg-McQueen, Black Mesa Technologies LLC * http://www.blackmesatech.com * http://cmsmcq.com/mib * http://balisage.net ****************************************************************
Received on Thursday, 18 October 2012 02:52:02 UTC