[BLD] comments on the semantics of lists

Harold,

I had a closer look at your proposal for the semantics of lists in RIF 
[1].  I have a few comments:

The symbol nil is not defined.  It should probably be something like 
"the domain of every RIF structure I contains an object nil".

The function pair is not defined.  It should probably be something like 
"every RIF structure contains a function pair: D x Dl -> Dl, where Dl is 
a subset of D comprising the object nil and the range of pair".

Apart from these two things, the proposal looks fine.

Best, Jos

[1] http://www.w3.org/2005/rules/wg/wiki/Core/List_Constructor
-- 
Jos de Bruijn            debruijn@inf.unibz.it
+390471016224         http://www.debruijn.net/
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