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Joe Fawcett wrote:
> I'm having trouble working out from
> http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/#anyURI
> [shown at bottom of mail]
> means that anyURI can be an empty string, can someone elucidate?
If it couldn't, it would be wrong. An empty string is a valid URI.
Bob Foster
> Thanks
>
> Joe
>
>
> Definition:
> 3.2.17 anyURI
> [Definition:] anyURI represents a Uniform Resource Identifier Reference
> (URI). An anyURI value can be absolute or relative, and may have an
optional
> fragment identifier (i.e., it may be a URI Reference). This type
should be
> used to specify the intention that the value fulfills the role of a
URI as
> defined by [RFC 2396], as amended by [RFC 2732].
>
> The mapping from anyURI values to URIs is as defined in Section 5.4
Locator
> Attribute of [XML Linking Language] (see also Section 8 Character
Encoding
> in URI References of [Character Model]). This means that a wide range of
> internationalized resource identifiers can be specified when an anyURI is
> called for, and still be understood as URIs per [RFC 2396], as amended by
> [RFC 2732], where appropriate to identify resources.
>
> NOTE: Each URI scheme imposes specialized syntax rules for URIs in that
> scheme, including restrictions on the syntax of allowed fragement
> identifiers. Because it is impractical for processors to check that a
value
> is a context-appropriate URI reference, this specification follows
the lead
> of [RFC 2396] (as amended by [RFC 2732]) in this matter: such rules and
> restrictions are not part of type validity and are not checked by
·minimally
> conforming· processors. Thus in practice the above definition imposes
only
> very modest obligations on ·minimally conforming· processors.
> 3.2.17.1 Lexical representation
> The ·lexical space· of anyURI is finite-length character sequences which,
> when the algorithm defined in Section 5.4 of [XML Linking Language] is
> applied to them, result in strings which are legal URIs according to [RFC
> 2396], as amended by [RFC 2732].
>
> NOTE: Spaces are, in principle, allowed in the ·lexical space· of
anyURI,
> however, their use is highly discouraged (unless they are encoded by
%20).
> 3.2.17.2 Constraining facets
> anyURI has the following ·constraining facets·:
>
> a.. length
> b.. minLength
> c.. maxLength
> d.. pattern
> e.. enumeration
> f.. whiteSpace
>
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