[Fwd: [Bug 4888] Clarify text striping and consolidation of white space characters for nested xml:space]

-------- Original Message --------
Subject: [Bug 4888] Clarify text striping and consolidation of white 
space characters for nested xml:space
Date: Fri, 27 Jul 2007 19:32:06 +0000
From: bugzilla@wiggum.w3.org
To: schepers@w3.org

http://www.w3.org/Bugs/Public/show_bug.cgi?id=4888

            Summary: Clarify text striping and consolidation of white space
                     characters for nested xml:space
            Product: SVG
            Version: All Specifications
           Platform: All
         OS/Version: All
             Status: NEW
           Severity: normal
           Priority: P2
          Component: Text
         AssignedTo: schepers@w3.org
         ReportedBy: dtc-w3@scieneer.com
          QAContact: schepers@w3.org


Could the SVG specification clarify the handling of white space 
characters when
there are nested text elements that differ in their xml:space attribute.

When xml:space is 'default' the SVG specification requires the 
application to
'strip off all leading and trailing space characters', but also requires the
application to preserve leading and trailing white space characters when
xml:space is 'preserve'.  But what is expected when there are leading and
trailing
white space characters defined in a mixture of elements with xml:space of
'preserve'
and 'default'?

When xml:space is 'default' the SVG specification requires the 
application to
'all contiguous space characters will be consolidated', but also 
requires the
application to preserve white space characters when xml:space is 'preserve'.
But what is expected when there are white space characters to 
consolidate that
are defined in a mixture of elements with xml:space of 'preserve' and
'default'?

Suggested clarification:
When stripping leading and trailing white space characters, or consolidating
white
space characters, white space characters defined within a element with
xml:space
of "preserve" are not stripped or consolidated and they are recognized 
as white
space
characters for the purpose of stripping and consolidation and do not prevent
the
stripping or consolidation of adjacent white space characters defined in
elements
with xml:space="default".

Example:
Let 'P' represent a white space character defined in an element with 
xml:space
of 'preserve'.
Let 'D' represent a white space character defined in an element with 
xml:space
of 'default'.
Let 'T' represent non-space text characters.

Given the string "DPDPDTDDTPTDPTPDTDPDTPDPTDPDPD" the application will strip
and consolidate
the white space characters to give the string: "PPTDTPTPTPTPTPPTPP"

The current practice of SVG viewers appears to be to preserve white space
characters defined
within a xml:space="preserve" element even when mixed with adjacent 
whitespace
characters
defined in elements with xml:space="default".  However the handling of white
space characters
defined in elements with xml:space="default" varies widely when mixed with
adjacent whitespace
characters defined in elements with xml:space="preserve".



-- 

Regards-
-Doug Schepers
W3C Staff Contact, SVG, CDF, and WebAPI

Received on Friday, 27 July 2007 23:06:51 UTC