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From: Matthew Heaney <matthew_heaney@acm.org>
Subject: Re: Software landmines (loops)
Date: 1998/09/06
Message-ID: <m3k93h36ze.fsf@mheaney.ni.net>#1/1
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NNTP-Posting-Date: Sun, 06 Sep 1998 09:44:51 PDT
Newsgroups: comp.lang.eiffel,comp.object,comp.software-eng,comp.lang.ada
Date: 1998-09-06T00:00:00+00:00
List-Id: <comp.lang.ada>

Charles Hixson <charleshixsn@earthlink.net> writes:

> Early returns from routines frequently make them easier to understand. 
> And maintain.  Se/se is something that is worth moderate efforts.  It
> is, however, related to something else.  Something that I don't yet have
> words to wrap around, but lots of other people on this list seem to also
> feel it.

As Bob Eachus pointed out, we can't even agree on what "single exit"
means.  According to him, you could interpret that to mean that the
subprogram has a single point of return - to the point of call.

According to that interpretation, multiple returns from a subprogram do
indeed have a single exit, and thus fall under the rubric of "structured
programming."

I argue against using only a single return statement, because it often
means that you have to do work to do ... nothing.  Once I determine my
answer (or satisfy the conditions for loop termination), then I'd rather
return immediately, instead of having to figure out how to navigate my
way to the end of the subprogram.