RE: SVG paths in XSLT (was: Using W3C Regular Expressions)

["Bullard, Claude L (Len)" <clbullar@ingr.com>]

This points out something that recurs a lot and 
was noted often in the days before people were 
trained to think of markup languages as a single 
DTD or schema which everyone implements:  the 
need for an up/down transformable language spec.  
This approach was well-understood and documented 
in the past.

For a standard language there should be:

1. A form that is an up translation target.  The 
maximum information form into which and out of 
which other forms can be created.

2.  Specifications for compressed format.  These 
should be normatively expressed as the transform 
itself.  

In the SVG example, Henry's preferred form is 
the up form.  It is not terse, but it can be 
used for lossless description.  SVG with 
minimized paths is a compressed form, one 
of the possible normative compressed forms 
which could be documented by transform. 

The idea of identity equivalence should 
be relaxed to similarity by pattern where 
a pattern represents the ability to create 
a similar form.  Similarity does not infer 
isomorphic identity, only that the category 
or class can include its non-reversible 
forms as family members.

It seems trivial, but has implications for 
how we take specifications for languages 
and adopt them into flexible standards.
It changes our thinking from one of 
colonization and policy laundering to 
standardization the accepts the potential 
for family variants related by standard 
and normative transforms.

Len Bullard
Intergraph Public Safety
clbullar@ingr.com
http://www.mp3.com/LenBullard

Ekam sat.h, Vipraah bahudhaa vadanti.
Daamyata. Datta. Dayadhvam.h


-----Original Message-----
From: ht@cogsci.ed.ac.uk [mailto:ht@cogsci.ed.ac.uk]

I wanted to be able to go _the other way_, and without
_deeply_ tedious us of string functions and so in in XSLT I can't.
I agree that in principle the move we want to encourage is _out of_
other formats _into_ SVG, as you've done, but sometimes the other way
is necessary, and the actual application I had in mind was for
tutorial _display_ of SVG paths, i.e. SVG->HTML.