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From: craig@leland.Stanford.EDU (Craig Chambers)
Subject: Re: Functions without side effects (was Old confusion)
Message-ID: <1991May30.195249.16103@leland.Stanford.EDU>
Sender: news@leland.Stanford.EDU (Mr News)
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Organization: Stanford University
References:  <1991May30.141218.3446@mstr.hgc.edu>
Date: Thu, 30 May 91 19:52:49 GMT
Lines: 16

In article <1991May30.141218.3446@mstr.hgc.edu>, jcm@mstr.hgc.edu (James McKim) writes:
|> The point is pop and top are independently useful and so deserve to be separated.

I agree; I never meant to suggest that Top shouldn't exist.

|> And this independent usefulness comes about precisely because one changes
|> the state and the other merely queries.

No, my Stack class would have a Top method that returned the top of
the stack and a Pop method that both removed the top element from the
stack *and returned this element to me*.  Since I don't follow any
dogma stating that procedures should not return values, I make my
procedures be as helpful as possible, in this case by also returning
what the top of the stack was.

-- Craig Chambers