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Re: a question about <forall> element

From: Stan Devitt <jsdevitt@stratumtek.com>
Date: Wed, 07 May 2003 17:20:51 -0400
Message-ID: <3EB978B3.6000608@stratumtek.com>
To: Robert Miner <RobertM@dessci.com>
CC: Strotmann@rrz.uni-koeln.de, www-math@w3.org

Note that the signatures in Appendix C are  not "exhaustive" so
that in particular, there probably should have been an example with 
something
other than an apply.

Csymbols should be  allowed as arguments any place an apply might be used
as an argument ( since you can always fake it using applying the 
identity function
to the csymbol ... )

A slight change in the wording of this paragraph so that it becomes 
illustrative
rather than prescriptive plus the inclusion of one or more extra example 
signatures
would probably resolve the issue (for this specific case ...) 

As Andreas has pointed out, the general issue of being too prescriptive
has been come up before.

Stan Devitt

Robert Miner wrote:

>Hi Andreas,
>
>  
>
>>The misunderstanding may be about <forall/> being required to be used 
>>within the context of an apply element.  That refers to the apply 
>>element within which the forall element is embedded, however, and 
>>therefore there is no problem if there is no apply element as a sibling 
>>of the forall element.
>>    
>>
>
>That may be the sensible interpretation, but it isn't how the spec is
>written.  From 4.3.17:
>
>  "The forall element represents the universal quantifier of logic. It
>  must be used in conjunction with one or more bound variables, an
>  optional condition element, and an assertion, which should take the
>  form of an apply element. In MathML 1.0, the reln element was also
>  permitted here: this usage is now deprecated."
>
>And from the validation grammer, C.2.3.18:
>
>  "Signature 
>
>    (bvar*,condition?,apply) -> boolean 
>    (bvar*,condition?,(reln)) -> boolean "
>
>--Robert
>
>------------------------------------------------------------------
>Dr. Robert Miner                                RobertM@dessci.com
>MathML 2.0 Specification Co-editor                    651-223-2883
>Design Science, Inc.   "How Science Communicates"   www.dessci.com
>------------------------------------------------------------------
>
>
>
>
>
>
>  
>
Received on Wednesday, 7 May 2003 17:18:19 GMT

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