From: "David A. Black" <dblack@...>
Date: 2008-08-24T11:26:52+09:00
Subject: Re: Why 'if 0' succeeds in Ruby

Hi Ed --

On Sun, 24 Aug 2008, M. Edward (Ed) Borasky wrote:

> On Sun, 2008-08-24 at 02:31 +0900, Dave Bass wrote:
>> But unfortunately Ruby regards both false and nil as not-true. For some
>> reason, this is touted as a feature.
>>
>> False and nil are two quite different concepts and should not be
>> conflated.
>
> Exactly! To make matters worse, Lisp "traditionally" treated nil as
> false, but Scheme has "true", "false" and "nil" and nil is treated as
> true in Scheme.
>
> So I don't have a problem with 0 not being false, but I do have a
> problem with nil being false in Lisp and Ruby and true in Scheme. 0 is
> 0, nil is nil, true is true and false is false and that is that!
>
> :)

I understand what you're saying but I have a real, non-rhetorical
question: In practical terms, what do you think should be done about
such a situation? It seems to me that there are two possibilities:
either computer languages really do things differently, including
things like this (not just stylistic and/or cosmetic things), or they
don't and then they all become the same.

I can't think of a third possibility, and of course I like the first
better than the second :-)


David

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