RE: [LC-2166] RE: Feedback of EXI specification 3

Hi Ishizaki-san,

The value of xsi:type attribute is represented as QName, instead of
as a String. This is an exception, and should not pose the processing
efficiency overhead that the WG is wary of, because xsi:type is the
first attribute that comes after namespace declarations in EXI streams.

Please see the note in the description of grammar syntax in section
"8.5.4.4.2 Adding Productions when Strict is True" for the definition
of AT(xsi:type) representation.

Hope it helps,

-taki


-----Original Message-----
From: ISHIZAKI Tooru [mailto:ishizaki.tooru@canon.co.jp]
Sent: Tuesday, January 27, 2009 5:08 PM
To: Taki Kamiya; public-exi-comments@w3.org
Cc: youenn.fablet@crf.canon.fr; fujisawa.jun@canon.co.jp
Subject: Re: [LC-2166] RE: Feedback of EXI specification 3

Hi Taki-san, and WG members,

Thank you very much.
I understood why value qnames are not represented using
enumeration encoding.

And I have one unclear point. Please let me know.
For example, there is below value qname description.

xsi:type="xd:string"

If value qname is represented as a string, on Preserve.prefixes=false,
is it difficult to find the namespace of "xd"?

Best Regards,
Tooru Ishizaki.

> Hi Tooru,
>
> Value qnames are represented as strings in EXI format. Because prefixes used
> in an instance and its corresponding schema are declared in each document
> independently from the other, enumerated values in schema are of little use for
> types derived from xsd:QName since value qnames in EXI streams are strings.
> Note, however, that markup qnames which occur as the names of elements
> and attributes are represented using built-in QName datatype representation [1].
>
> The rationale for the use of strings as the representation of value qnames
> is primarily so as to avoid the anticipated processing efficiency overhead that
> is likely to be involved if we used built-in QName datatype representation for
> value qnames. This concern of processing efficiency overhead is particular to
> value qnames, and is not foreseen for markup qnames. Therefore we use built-in
> QName datatype representation for markup qnames.
>
> In reviewing the spec to answer your question, we have found an omission
> in the table that defines the default relationship between the schema datatypes
> and built-in EXI datatypes [2]. XML Schema type xsd:QName and xsd:NOTATION
> need to be added to the type list in the row of string datatype representation.
>
> [1] http://www.w3.org/TR/2008/WD-exi-20080919/#encodingQName
> [2] http://www.w3.org/TR/2008/WD-exi-20080919/#builtInEXITypes
>
> Hope it helps,
>
> -taki
>
>
> -----Original Message-----
> From: public-exi-comments-request@w3.org [mailto:public-exi-comments-request@w3.org] On Behalf Of ISHIZAKI Tooru
> Sent: Thursday, November 06, 2008 2:23 AM
> To: public-exi-comments@w3.org
> Cc: youenn.fablet@crf.canon.fr; fujisawa.jun@canon.co.jp
> Subject: Feedback of EXI specification 3
>
>
> Dear EXI members,
>
> I have a feedback of EXI specification.
> In chapter 7.2(Enumerations), why can't the enumeration type
>  be applied for QName?
>
> Best Regards,
> Tooru Ishizaki.
>
> --
> TOORU Ishizaki <ishizaki.tooru@canon.co.jp>
>
>


--
TOORU Ishizaki <ishizaki.tooru@canon.co.jp>

Received on Wednesday, 11 February 2009 19:42:40 UTC