From mboxrd@z Thu Jan  1 00:00:00 1970
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From: "W. Wesley Groleau (Wes)" <wwgrol@PSERC041.FW.HAC.COM>
Subject: Is this correct?
Date: 1996/05/02
Message-ID: <9605022151.AA12098@most>#1/1
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sender: Ada programming language <INFO-ADA@VM1.NoDak.EDU>
comments: Gated by NETNEWS@AUVM.AMERICAN.EDU
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Date: 1996-05-02T00:00:00+00:00
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I'm not saying where this comes from.  If you know, please
keep it to yourself and certainly don't flame the author.

It seems to me that the following won't work.  Or are the
comments (all added by me) inaccurate?


  function "="(Left : Stack; Right : Stack) return Boolean is

   LC    : Container_Pointer := Left.Head ;   -- what if either
   RC    : Container_Pointer := Right.Head ;  -- is null before call?
   Equal : Boolean := True ;                 -- (caller gets exception)

  begin -- "="

    loop

      Equal := LC.Value = RC.Value ;

      LC := LC.Next ;
      RC := RC.Next ;

      exit when (LC = null or RC = null) or not Equal ;
      -- I suspect a typo because parentheses are unnecessary
      -- If top three items are equal, but only Right has a fourth, then
      -- exit because LC = null and return True (incorrect).

    end loop ;

    return Equal ;

  end "=";