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From: Patrick Logan <plogan@user2.teleport.com>
Subject: Re: Software landmines (loops)
Date: 1998/09/03
Message-ID: <NkCH1.7426$f01.5336532@news.teleport.com>#1/1
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Organization: Teleport - Portland's Public Access (503) 220-1016
NNTP-Posting-Date: Thu, 03 Sep 1998 12:44:45 PDT
Newsgroups: comp.lang.eiffel,comp.object,comp.software-eng,comp.lang.ada
Date: 1998-09-03T00:00:00+00:00
List-Id: <comp.lang.ada>

In comp.object sureshvv@hotmail.com wrote:

: > >void AFunction(...)
: > >{
: > >  if not (SomeCondition)    and
: > >     not (AnotherCondition) and
: > >     not (AThirdCondition)  then
: > >
: > >  // now do the real work...
: > >
: > >  endif
: > >  return;
: > >}

: Note that this has added a level of nesting to the real work (tm). Now also
: consider the case where you might have to return different error conditions
: to the calling routine. And/Or you have to output some message to a log file
: for each of the conditions.

If I have to do something like this, I usually put the body in its own
method that does not have these checks at all, something like this...

void AFunction(...)
{
  if (someCondition) {
    throw ...
  } else if (anotherCondition) {
    throw ...
  } else if (aThirdCondition) {
    throw ...
  } else if (...) {
    throw ...
  } else {
    AFunctionWithGoodStanding(...)
  }
}

void AFunctionWithGoodStanding(...)
{
  ...do the real stuff...
}

Then it is clear the first function's purpose is to get all the issues
out of the way and the second function's purpose is to do the work.

-- 
Patrick Logan    (H) mailto:plogan@teleport.com 
                 (W) mailto:patrickl@gemstone.com 
                 http://www.gemstone.com