Path: utzoo!attcan!uunet!cs.utexas.edu!samsung!rex!fs
From: fs@rex.cs.tulane.edu (Frank Silbermann)
Newsgroups: comp.lang.functional
Subject: Re: BOTTOM !== NONTERMINATION
Message-ID: <3944@rex.cs.tulane.edu>
Date: 27 Jul 90 18:50:08 GMT
References: <23593@megaron.cs.arizona.edu>
Organization: Computer Science Dept., Tulane Univ., New Orleans, LA
Lines: 35


<23593@megaron.cs.arizona.edu> gudeman@cs.arizona.edu (David Gudeman):
>	I don't think you understand what I'm saying.
>	I suggesting that (1) the denotational semantics
>	are intended to give a rigorous mathematical meaning to a program.

And, in the case of "functional" languages,
to show just in what sense the language is functional
(i.e. do the "function definitions" actually denote functions).

>	(2) it would be nice if the interpreter for the language was
>	--in some sense-- an implementation of the semantics.

>	(3) if you identify all error results together in the semantics,
>	then the interpreter is _not_ an implementation of the semantics,
>	because the interpreter (hopefully) produces informative
>	messages on errors.

Depends on whether you consider these messages to be metalogical
comments _about_ the interpretation,
or whether error messages are considered to be
_part of_ the interpretation,
i.e.  data that other parts of the program can use.

>	I know what "declarative" and "functional" mean (as well as anyone).
>	I don't think they are synonyms for "good".
>...	I'm not religious about functional programming
>	but I'm interested in it; so I guess the answer is that
>	I'm not a member of the church, but I attend services
>	on the off chance that it might be good for my soul.

Well said!

	Frank Silbermann	fs@rex.cs.tulane.edu
	Tulane University	New Orleans, Louisianna  USA