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Re: xsd:string required?

From: <Noah_Mendelsohn@lotus.com>
Date: Mon, 7 Aug 2000 14:13:37 -0400
To: Liz Castro <lcastro@cookwood.com>
Cc: www-xml-schema-comments@w3.org
Message-ID: <OF34886794.1801EB25-ON85256934.0063F76F@lotus.com>
Liz Castro writes: 

>> I understand how BOB (or whatever) can be the namespace 
>> for element names, but I don't think it is at all obvious 
>> why it should be part of the value of an attribute.

This is explained in the schema structures specification section "4.2 References to Schema Components"[1].  There you will find the text:

"Reference to schema components from a schema document is managed in a 
uniform way, whether the component corresponds to an element information 
item from the same schema document or is imported (References to schema components across namespaces (6.2.2)) from an external schema (which may, but need not, correspond to an 
actual schema document). The form of all such references is a QName. In each of the XML representation expositions in the following sections, 
an attribute is shown as having type QName if and only if it is interpreted as referencing a schema component."

So, the references about which you are inquiring are encoded using a 
mechanism invented specifically for use in schemas (though it could be 
generalized), and which is understood and interpreted by schema aware 
processors interpreting schema documents (and also xsi:type attributes in 
instance documents).   Note also that the datatype specification provides 
a formal definition for a QName datatype[2], and that definition is 
referenced by the schema for schemas.  In other words, the attributes you 
asked about our formally typed as QNames.  I hope this helps.

[1] http://www.w3.org/TR/xmlschema-1/#refSchemaConstructs
[2] http://www.w3.org/TR/xmlschema-2/#QName

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Noah Mendelsohn                                    Voice: 1-617-693-4036
Lotus Development Corp.                            Fax: 1-617-693-8676
One Rogers Street
Cambridge, MA 02142
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Received on Monday, 7 August 2000 14:14:47 UTC

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