Re: List of union

"Michael Marchegay" <mmarcheg@optonline.net> writes:

> My understanding of the concept of list, as defined in XML Schema
> recommendation, would make me think that a list whose {item type definition}
> has the variety union is valid only if the union does not contain any simple
> type definitions having the variety list among its {member type
> definitions}.
> 
> I looked in the XML Schema Part 1 and 2 for some text confirming that, but I
> haven't found it.  I also looked in the archives of xmlschema-dev list for
> an explanation, and I have found confirmation of my hypothesis, but none of
> the answers refere to a clause stating it clearly.  Is this restriction
> explained somewhere in the recommendation?

In Schema Component Constraint: Derivation Valid (Restriction, Simple) [1]

   "2 If the {variety} is list, then  all of the following must be true:
      2.1 The {item type definition} must have a {variety} of atomic
      or union (in which case all the {member type definitions} must
      be atomic)."

ht

[1] http://www.w3.org/TR/xmlschema-1/#cos-st-restricts
-- 
  Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
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Received on Thursday, 3 April 2003 03:37:18 UTC