Copy for the records: LC issue 59

The following message was sent to the commentator on July 11th; no reply was
received.

//Mary

From: "Mary Holstege" <holstege@calico.com>
To: ddj@mclink.it
Subject: XML Schemas Last Call Issue 59
Date: Tue, 11 Jul 2000 11:38:30 -0700
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I have been asked to respond on behalf XML Schemas Working Group about your
comments on user-defined list separators, which we have categorized as 
LC issue 59 [1]

You raised the issue:
> The proposals first. The first one is related to lists of strings (simple
> types). Standards state that no list of string can be defined if some string
> contain spaces, because list are space separators. In my personal opinion
> this is a weakness of the standard, especially if you consider that we are
> speaking of Unicode strings, where the concept (and code point) of space may
> differ from language to language. What about adding a new facet for simple
> types which allow to specify the list separator? Default would be blank 
> space 0x20. 

The working group took up this issue at our last face-to-face meeting. 

There was some support for the notion of allowing a user-defined separator
character, the argument being offered that it was a small thing, that most
languages with which one would implement schemas already supported a
tokenization routine that permitted alternative token separator characters, and
that it was indeed useful. 

The consensus of the group was that the space-separated list types were put in
place only to support some legacy XML types, and that this was a slippery slope
we did not wish to embark on. (A single character or a character set? A
character set or a string? A set of strings? A pattern parsing language?) 
In general we have been careful to avoid structured simple strings, and a
general guiding design principal has been that structured markup be done in XML
syntax. There are concerns that such "microparsing" requires the presence of a
schema in order to usefully process the information at all if the schema
defines the lexical syntax in this way. The group is therefore unwilling at
this time to tackle the issues relating to structured simple types.

Please let us know if you still object to this decision.

[1] http://www.w3.org/2000/05/12-xmlschema-lcissues.html

	-- Mary
	   Holstege@calico.com

| Mary Holstege, PhD
| Distinguished Engineer                  holstege@calico.COM
| Calico Commerce                         (408) 278-7367
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Received on Wednesday, 20 September 2000 07:50:48 UTC