# [om] a couple of questions

Andrew Solomon andrew at illywhacker.net
Tue Apr 17 20:32:26 CEST 2001

Ok, so I propose introducing a new cd "fns2" with
and the following expresses the tautology "a \in {a,b}".

How does that sound?

Andrew

<OMOBJ>
<OMBIND>
<OMS cd="fns2" name="constant"/>
<OMBVAR>
<OMV name="a"/>
<OMV name="b"/>
</OMBVAR>
<OMA>
<OMS cd="set1" name="in"/>
<OMV name="a"/>
<OMA>
<OMS cd="set1" name="set"/>
<OMV name="a"/>
<OMV name="b"/>
</OMA>
</OMA>
</OMBIND>
</OMOBJ>
On Tue, Apr 17, 2001 at 07:25:13AM -0700, Stephen Braham wrote:
>
>
> Steve Linton wrote:
> >
> > The nicest solution perhaps would be to define a binding constructor for
> > defining a finite set of bound variables. Then you could create a scope in
> > which a, b, and c where the bound variables of this constructor, and even
> > non-CD reading applications would know that only the names of a b and c were
> > meaningful, and how far that meaning extended.
> >
> >         steve
>
> I'd go even stronger and say this is the ONLY way to do things. For
> the semantic meaning to be preserved, there must be a corresponding
> Lambda construction to isolate the defining variables.
>
> Just as OMSTR is a cheat, so can using OMV's on their own be a cheat.
> Generally, if the OMV isn't going to be referred to in an external
> statement, it generally should be bound.
>
> Indeed, I'd say that's why we decided to have bindings explicit in the
> language!
>
> 				Steve
>
> --
> Stephen P. Braham			Director, PolyLAB
> warp at polylab.sfu.ca			TIME Centre
> (604) 268-7981				Simon Fraser University
> (fax) 268-7980				Harbour Centre Campus
>
>    PolyLAB: From the Classroom to Space, http://polylab.sfu.ca/
>

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