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From: pereira@research.att.com (Fernando Pereira)
Subject: Re: expand_term (was: Re: Is Visual Prolog "real" Prolog?)
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Date: Mon, 20 May 1996 22:57:25 GMT
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In article <4npgg4$d9c@news.irisa.fr>, ridoux@irisa.fr wrote:
> [ Fernando Pereira said originally]
> |> >However, metaprogramming in lambda Prolog still requires explicit encoding
> |> >of object-level formulas as metalevel terms, because of the type system.
> |> >In the original implementation of lambda Prolog, this could be avoided by
> |> >using runtime type polymorphism, but at considerable danger of
> |> >nontermination because of underconstrained types in higher-order
> |> >unification. More recent implementations use stricter type systems, so
> |> >encoding is inevitable.
> [Fergus Henderson said]
> |> Could you please explain this in a little bit more detail, with say an
> |> example or two?
> 
> I do not know to which work Fernando is alluding to, but let me offer an
> explanation.  
[Excellent explanation]
That's exactly the difficulty I had in mind, but you put it more clearly
than I could have, thanks.
