RE: Variable name type change in VoiceXML 2.1 CR

David,

Thanks for your observation. The Voice Browser Working Group agrees that the revised schema is too restrictive, and it will be fixed in a forthcoming update to the VoiceXML 2.1 specification.

Sincerely,

Matt Oshry

-----Original Message-----
From: www-voice-request@w3.org [mailto:www-voice-request@w3.org] On Behalf Of David Scarratt
Sent: Tuesday, January 17, 2006 9:15 PM
To: www-voice@w3.org
Subject: Variable name type change in VoiceXML 2.1 CR


The type 'RestrictedVariableName.datatype' in vxml-datatypes.xsd changed from being

   <xsd:restriction base="xsd:NMTOKEN">
   </xsd:restriction>

(the same as for VoiceXML 2.0) in the VoiceXML 2.1 20040728 working draft schema to

  <xsd:restriction base="xsd:token">
   <xsd:pattern value="([a-zA-Z]|[a-zA-Z$][a-zA-Z0-9_$]*[a-zA-Z0-9_])"/>
  </xsd:restriction>

in the VoiceXML 2.1 candidate recommendation schema, but I can find no comment about the change.  It seems intended to implement some of the additional constraints listed in the accompanying 'xsd:documentation' 
section; but since the VoiceXML 2.0 specification indicates that "the variable naming convention is as in ECMAScript", which allows Unicode letters in names, while the new pattern apparently restricts variable names to a subset of ASCII, it breaks backwards compatibility.

For example, the following document is a conforming VoiceXML 2.0 document, but the same document with "version='2.1'" (and correct schema
location) would not be a conforming VoiceXML 2.1 document:

   <?xml version="1.0" encoding="iso8859-1"?>
   <vxml version="2.0" xmlns="http://www.w3.org/2001/vxml"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://www.w3.org/2001/vxml
     http://www.w3.org/TR/voicexml20/vxml.xsd">

     <var name="café"/>
     <form>
       <block>hello</block>
     </form>

   </vxml>

Could someone clarify this for me?

Thanks.
--
David Scarratt
Senior Engineer, Holly Connects
david.scarratt@holly-connects.com

Received on Friday, 20 January 2006 08:29:25 UTC