- From: Jeni Tennison <jeni@jenitennison.com>
- Date: Fri, 17 May 2002 17:42:42 +0100
- To: Mark Feblowitz <mfeblowitz@frictionless.com>
- CC: Tom Moog <tmoog@sarvega.com>, xmlschema-dev@w3.org
Hi Mark, > Would the same be the case for sequences? You mean is a sequence with no content and a minOccurs of more than 1 unsatisfiable? No. Sequences and all groups are different from choices. The section that I quoted actually goes on to address sequences and all groups specifically: "Nothing in the above should be understood as ruling out groups whose {particles} is empty: although no sequence can be ·valid· with respect to such a group whose {compositor} is choice, the empty sequence is ·valid· with respect to empty groups whose {compositor} is sequence or all." (Note that in the above most of the references to "sequence" are talking about the sequence of elements in the content of the instance document, not sequence groups in the schema.) The difference between sequences and choices is that for sequences the rule is: All the particles in the sequence must be present in the instance, in the order specified. such that if there aren't any particles in the sequence, that's fine, whereas for choices the rule is: One of the particles in the choice must be present in the instance. such that if there aren't any particles in the choice, then this can't be satisfied. Cheers, Jeni --- Jeni Tennison http://www.jenitennison.com/
Received on Friday, 17 May 2002 12:42:47 UTC