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John Cowan wrote: > Bob Wyman scripsit: >>It would have been wise if the WXS designers had noted existing >>standards and used "SET" rather than "SEQUENCE" when defining WXS... > > There's a reason behind that: the schema-centric viewpoint on this point > is opposed to the data-centric viewpoint. In general, if a schema says > that the order is prescribed (a sequence), that means that there is no > significance in the order. On the other hand, if the schema does not > prescribe an order, then there is typically significance in the ordering > that actually appears in the data. WXS takes a schema-centric viewpoint; > ASN.1 takes a data-centric one. As was pointed out earlier, the "schema-centric" view is missing the ability to say, for elements, that no order is prescribed and order is not significant. Same semantics as attributes. OTOH, if a schema prescribes an order (a sequence) it is moot that there is no significance in the order, as the prescribed order must be observed. Further, the schema-centric viewpoint you describe is definitely not the common usage for iterated choices, e.g., (a|b|...)*. In this case, no order (or cardinality) are prescribed and the semantics is usually that order is not significant. Bob Foster
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