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From: brnstnd@kramden.acf.nyu.edu (Dan Bernstein)
Newsgroups: comp.lang.misc
Subject: Re: Dynamic typing (part 3)
Message-ID: <24547:Mar1506:28:2591@kramden.acf.nyu.edu>
Date: 15 Mar 91 06:28:25 GMT
References: <626@optima.cs.arizona.edu> <1991Mar14.183323.27020@engage.enet.dec.com>
Organization: IR
Lines: 23

In article <1991Mar14.183323.27020@engage.enet.dec.com> grier@marx.enet.dec.com () writes:
> In article <626@optima.cs.arizona.edu>, gudeman@cs.arizona.edu (David
> Gudeman) writes:
> |> In article  <1991Mar13.163629.12630@engage.enet.dec.com>
> |> grier@marx.enet.dec.com writes:
> |> ]   In mathematics, it makes NO sense to talk about applying a
> |> function
> |> ]or operation to a symbol unless the symbol is known to be in the
> |> ]domain of the operation/function.  I.e. writing something like "for
> |> all
> |> ]x, exp(x) is greater than zero" is nonsense.
> |> Nonsense.  Anybody with a clue immediately understands that x is
> |> restricted to values in the domain of exp.
>    Wrong.

No, you're wrong. Suppes, for example, defines functions so that you can
say ``The set of x such that exp(x) is smaller than or equal to zero is
empty.'' You don't have to qualify x as ``x in the reals'' for the
statement to make sense and be perfectly correct.

What this has to do with dynamic typing is beyond me.

---Dan