[ebBP] 3/28/2004: WI-57-44 Use of and constraints for white space(xsd: string)

["Monica J. Martin" <Monica.Martin@Sun.COM>]

Discussion|OASIS.ebBP.WI57-White space usage and constraints;
Topic|;
Point|Request for summary assistance;

mm1@
Sacha,
Can you take the work items 44 and 57 and provide a summary of your 
input and recommendations in preparation for the OASIS symposium and TC 
discussion in April 2004?

Reference:
Work Item 44 - Constraints on white space - Should constraints be placed 
on the use of xsd:string in usage in BPSS or left to implementation and 
deployment?
Work Item 57 - Use of white space in xsd:string - Define what facets, if 
any should be used on the data types used on all or specific BPSS 
elements. In XSD, the xsd:string can use preserve, collapse and replace 
whitespace facets to ensure consistency. What should the BPSS use?

The recommendation discussed on the ebXML CPPA-negotiation list and 
provided to ebBP is shown below.

I encourage team comments here. Thanks.

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Schlegel: I looked up the XML Schema Part 2: Datatypes (W3C 
Recommendation 02 May 2001) from 
http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/
-------------
Section 3.2.1 string

The XML Schema "string" primitive type has constraning facets, such as 
length, minLength, maxLength, ... and whiteSpace.

There is a XML built in datatpye derived from string called 
"normalizedString"

Section 4.3.6 whiteSpace
The whiteSpace constraint can have 3 values: preserve, replace, and 
collapse.

preserve: no normalisation is done.
replace: tabs, line feed and carriage returns are replaced with space
!collapse: contiguous sequences of spaces are collapsed to a single
space. and leading and trailing spaces are removed.

It goes on that the string datatype has whiteSpace set as preserve. A 
derived by restriction of string data type can have the whiteSpace set
to collapse.

When I look at the BPSS v1.01 XML Schema I only see the usage of  
"xsd:string" data type without any constraints, such as whiteSpace.

It seems to me that the double white space in one of the expression 
attributes of a Transition element of the ANCPA BPSS is a problem
because it is of xsd:string which has whitespace set a preserved.

So "abc def" is not equal to "abc  def" if the whiteSpace constraint is 
set to preserved.
==========================================================================================================
@mm1