Re: [ACTION-64] Changes to CURIE spec to address prefix support

Greetings Shane, looks good to me. 

One thought, we might consider adding an informative appendix explaining 
how the prefix mapping could be done using xmlns: 

Regards, Roland



From:
Shane McCarron <shane@aptest.com>
To:
XHTML WG <public-xhtml2@w3.org>
Date:
25/03/2009 14:19
Subject:
[ACTION-64] Changes to CURIE spec to address prefix support



As per the resolution at the last vF2F, below is my proposal for 
changing the requirements in the CURIE specification so it avoids @xmlns 
altogether, instead relying upon the host language to define the prefix 
mapping mechanism.  These changes are against the current CR [1].

Section 3, paragraph 3 - 5, change from:

    When CURIES are used in an XML-based host language, and that host
    language supports XML Namespaces, prefix values MUST be able to be
    defined using the 'xmlns:' syntax specified in [XMLNAMES
    <http://www.w3.org/TR/curie/#ref_XMLNAMES>]. Such host languages MAY
    also provide additional prefix mapping definition mechanisms.

    The XML Namespaces specification states that prefix names are not
    permitted to begin with the characters 'xml' (see Leading XML
    <http://www.w3.org/TR/1999/REC-xml-names-19990114/#xmlReserved>).
    While this specification does not impose such a restriction, when
    CURIEs are used in an XML language this restriction is effectively
    inherited from XML Namespaces. If such a language defines an
    additional mechanism for defining prefixes, that mechanism SHOULD
    impose a similar restriction so there is no possibility of conflict
    between prefixes defined using the two mechanisms.

    When CURIES are used in a non-XML host language, the host language
    MUST provide a mechanism for defining the mapping from the |prefix|
    to an IRI.

To read:

    When CURIEs are used in a host language, the host language MUST
    provide one or more mechanisms for mapping from a prefix to an IRI.

Section 3, paragraphs 7-8, change from:

    A host language MAY declare a default prefix value, or MAY provide a
    mechanism for defining a default prefix value. This default prefix
    value MAY be different than the language's default namespace. In
    such a host language, when the |prefix| is omitted from a CURIE, the
    default prefix value MUST be used. Conversely, if such a language
    does not define a default prefix value mechanism and does not define
    a set of reserved values, CURIEs MUST NOT be used without a leading
    /prefix/ and colon.

    Host languages that support XML Namespaces always have a default
    namespace. This default namespace MUST NOT be used as the default
    prefix for CURIEs because the default namespace in such a language
    can change at any time in a document, and such a change would mean
    that seemingly identical CURIEs might map to different IRIs.

To read:

    A host language MAY declare a default prefix value, or MAY provide a
    mechanism for defining a default prefix value.  In such a host
    language, when the prefix is omitted from a CURIE, the default
    prefix value MUST be used.  Conversely, if such a language does not
    define a default prefix value mechanism and does not define a set of
    reserved values, CURIEs MUST NOT be used without a leading prefix
    and colon.

In other words, remove the references to XML namespaces and their 
attendant issues since we are not requiring them.

Also, I imagine that we should remove the reference to XMLNAMES 
altogether, since we no longer use it at all.

[1]  http://www.w3.org/TR/curie

-- 
Shane P. McCarron                          Phone: +1 763 786-8160 x120
Managing Director                            Fax: +1 763 786-8180
ApTest Minnesota                            Inet: shane@aptest.com










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