RE: How to use CDBase URIs in Content MathML?

I can add that at the time, a list of pros and cons of specifying the cdbase through a cdgroup on the <math> element was:

 - delegated to the existing OM cdgroup mechanism
 - allows easy mechanism for system-specific or host document control of cdbases
 - allows shorter, more efficient markup
 - allows CDs to move around without changing markup

 - comes at the cost of extra files, network traffic and harder comparisons
 - requires aliases when multiple CDs have the same name but different cdbases

--Robert

> -----Original Message-----
> From: www-math-request@w3.org [mailto:www-math-request@w3.org] On
> Behalf Of David Carlisle
> Sent: Monday, July 12, 2010 9:15 AM
> To: Christoph LANGE
> Cc: Urs Holzer; www-math@w3.org
> Subject: Re: How to use CDBase URIs in Content MathML?
> 
> On 12/07/2010 14:30, Christoph LANGE wrote:
> 
> > OK, but I'm still confused:  How would I translate the following to
> Content
> > MathML?
> >
> > <OMOBJ>
> >    <OMA>
> >      <OMS cdbase="http://example.org/cd" cd="foo" name="bar"/>
> >      <OMS cdbase="http://somewhere.com/cd" cd="foo" name="baz"/>
> >      <OMS cdbase="http://frobnitz.org/cd" cd="foo" name="fnord"/>
> >    </OMA>
> > </OMOBJ>
> >
> > I.e. what do I do when one formula uses symbols from CDs that have
> the same
> > relative name but under different CDBase URIs?
> >
> > And why is there no csymbol/@cdbase?
> 
> We went through 1001 permutations of specifying how cdbase and
> inherited
> attributes and compatibility with mathml2 markup were supposed to work
> and in the end came to the version in the current draft (earlier drafts
> before the 1st last call had different variants as I recall)
> 
> cdgroup files dont currently allow aliasing[although see below] so
> currently you would need to set up the alias externally, that is you
> could have the mathml
> 
> 
> <math cdbase="http://example.com/mycdgroup.xml">
>    <apply>
>      <csymbol cd="foo1">bar</csymbol>
>      <csymbol cd="foo2">baz</csymbol>
>      <csymbol cd="foo3">fnord</csymbol>
>    </apply>
> </math>
> 
> with the mycdgroup.xml group file referring to renamed copies of the
> original cd files (either actual copies or some kind of server redirect
> set up at example.com.
> 
> 
> the cdbase property is an optional openmath property in openmath2 and
> not there at all in openmath 1, and while it's useful as a location aid
> to find cd files I've never seen it used in practice to disambiguate cd
> files of the same name. The OpenMath CD review system has always
> assumed
> so far that any public CDs have unique names (hence the numbered names
> arith1, arith2 etc to allow easily naming variants)
> 
> so while the need to rename the files is a theoretical wart hopefully
> it
> isn't an issue in practice. Even in the OM syntax, if there is a real
> possibility of those three cds being used together, then giving them
> different names would probably be a good idea.
> 
> David
> 
> [note]
> 
> Arguably cdgroups do allow aliasing as the OM standard never actually
> says that the CDName and CDURI in a cdgroup file have to match up, so
> if
> you were to take a forgving interpretation of
> 
> http://www.openmath.org/standard/om20-2004-06-30/omstd20html-

> 4.xml#ssec_cdgroups
> 
> then you could mark up your example as above but instead of
> copying/redirecting the files at the http server level you could
> specify
> it in the cdgroup file as
> 
> 
> <CDGroup>
> <CDGroupMember>
> <CDName>foo1</CDName>
> <CDURL>http://example.org/cd/foo</CDURL>
> </CDGroupMember>
> <CDGroupMember>
> <CDName>foo2</CDName>
> <CDURL>http://somewhere.com/cd/foo</CDURL>
> </CDGroupMember>
> <CDGroupMember>
> <CDName>foo3</CDName>
> <CDURL>http://frobnitz.org/cd/foo</CDURL>
> </CDGroupMember>
> </CDGroup>
> 
> 
> 
> 
> 
> David
> 
> 
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Received on Monday, 12 July 2010 14:40:26 UTC