RE: Section 8.5 clarification

Dear Youenn,
 
Thank you for your comments regarding the schema-informed grammars presented
in the EXI specification. The working group has reviewed your comments and
agrees the EXI specification should be clearer the schema mapping presented
in section 8.5 is only for the W3C XML Schema Language. We have updated
section 8.5 to state this fact more explicitly.
 
    Thank you again,
 
    John
 
John Schneider
AgileDelta, Inc.
 <mailto:john.schneider@agiledelta.com> john.schneider@agiledelta.com
 <http://www.agiledelta.com/> http://www.agiledelta.com
 


  _____  

From: public-exi-comments-request@w3.org
[mailto:public-exi-comments-request@w3.org] On Behalf Of FABLET Youenn
Sent: Wednesday, March 03, 2010 10:21 AM
To: public-exi-comments@w3.org
Subject: Section 8.5 clarification



Dear all,

 

Section 3 states that:

"The built-in EXI grammars accept any XML document or fragment and may be
augmented with productions derived from XML Schemas [XML Schema
<http://www.w3.org/TR/exi/#schema1> Structures]   [XML Schema
<http://www.w3.org/TR/exi/#schema2> Datatypes], RELAX NG schemas [ISO/IEC
19757-2:2003] <http://www.w3.org/TR/exi/#relaxng> , DTDs [XML 1.0]
<http://www.w3.org/TR/exi/#XML10>    [XML 1.1]
<http://www.w3.org/TR/exi/#XML11>  or other sources of information";

Section 5.4 states that : 

"Section  <http://www.w3.org/TR/exi/#informedGrammars> 8.5 Schema-informed
Grammars describes the system to derive schema-informed grammars from XML
Schemas."

Section 8.5 states that:

"This section describes the schema-informed grammars used by EXI when schema
information is available to describe the contents of the EXI stream
<http://www.w3.org/TR/exi/#key-existream> . Schema information used for
processing an EXI stream is either indicated by the header option schemaID
<http://www.w3.org/TR/exi/#key-schemaIDOption> , or communicated out-of-band
in the absence of schemaID <http://www.w3.org/TR/exi/#key-schemaIDOption> .
Schema-informed grammars are independent of any particular schema language
and can be derived from XML Schemas [XML Schema Structures]
<http://www.w3.org/TR/exi/#schema1>    [XML Schema Datatypes]
<http://www.w3.org/TR/exi/#schema2> , RELAX NG schemas [ISO/IEC
<http://www.w3.org/TR/exi/#relaxng> 19757-2:2003], DTDs [XML
<http://www.w3.org/TR/exi/#XML10> 1.0]   [XML 1.1]
<http://www.w3.org/TR/exi/#XML11>  or other schema languages for describing
what is likely to occur in an EXI stream. "

 

The exact meaning of these three sentences are somehow unclear when put
together. 

In particular it is easy to infer from the start of section 8.5 that this
section defines a mapping from several languages (XSD, RNG, DTD.), which is
not the case since the mapping is restricted to XSD only. On the contrary,
section 5.4 seems to induce that only XSD is supported currently (?).

 

It would be nice that, at a high level, the specification clearly states the
following two points:

-          This specification defines schema informed grammars that are
schema-neutral

-          This specification defines one mapping to schema informed
grammars, the input being XSD. 

Of course, the specification is free to state that other mappings can be
done.

 

The additional related comment I have is that section 8.5 defines both what
are schema-informed grammars and how to generate them from XSD.

The definition of the schema-informed grammars is tightly linked in the spec
to XSD words and concepts like GED for instance.

This is perfectly fine to me. However, to create another mapping, one would
need to rewrite something similar to the whole section 8.5.

Therefore the sentence quoted from section 8.5 could be clarified with that
respect.

 

Regards,

                Youenn