[Om3] binary vs n-ary relations

[Michael Kohlhase]

Professor James Davenport wrote:
> On Wed, September 24, 2008 9:32 pm, Paul Libbrecht wrote:
>   
>> Le 24-sept.-08 à 18:17, Professor James Davenport a écrit :
>>     
>>> Michael: I fear you're out-numbered.
>>>       
>> Well, careful James, I'm afraid MathML-2 spec counts as many voices
>> here...
>>     
> Possibly.
>   
>> Let's be pragmatic, how much are we breaking if we claim that strict-
>> MathML's relation symbols are binary only?
>>     
> I would hope nothing, but I worry about the cross-reference to 4.4.10
> from, e.g. file:///D:/MML3-draft/appendixc.html#cds.eq (my version is
> fairly old). 'eq' is NOT an associative operator.
>   
Well, MML3-draft is just that, a draft and it has language in the
beginning that anything in it may change at any time, so the reference
does not bother me.
>> This can certainly be part of the pragmatic to strict translation right?
>>     
> This would be an excellent idea.
>   
So can we get a consensus here? We have a telcon this afternoon, where
we can probably decide this. So if I interpret what I have seen, your
preference would be:

1. relation symbols are binary!!!!

2. we still have pragmatic MathML of the form
     <apply><eq/>a b c</apply>
     but that will be translated to
     <apply>
       <csymbol cd="logic1">and</csymbol>
       <apply><csymbol cd="relation1">eq</csmbol>a b</csmbol></apply>
       <apply><csymbol cd="relation1">eq</csmbol>b c</csmbol></apply>
     </apply>
     in the content to strict translation.

Michael
> James Davenport
> Hebron & Medlock Professor of Information Technology
> Formerly RAE Coordinator and Undergraduate Director of Studies, CS Dept
> Lecturer on CM30070, 30078, 50209, 50123, 50199
> Chairman, Powerful Computing WP, University of Bath
> OpenMath Content Dictionary Editor
> IMU Committee on Electronic Information and Communication
>
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>   

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