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NNTP-Posting-Date: Thu, 02 Oct 2008 07:56:59 -0500
Newsgroups: comp.lang.ada
Subject: Re: Avoiding side effects
References: <uljxa9o85.fsf@no.email.thanks.invalid>
From: Ole-Hjalmar Kristensen
 <ole-hjalmar.kristensen@substitute_employer_here.com>
Organization: Sun Microsystems
Date: 02 Oct 2008 14:56:58 +0200
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Date: 2008-10-02T14:56:58+02:00
List-Id: <comp.lang.ada>

If I understand your problem correctly, why not simply do the
following after the sort -u stage?:

comm -23 fileA fileB

But to answer the Ada quiestion, I think I would organize the loop a
little bit differently. The following is a classical way of merging
two files, but it should work in your case too:

  while not End_Of_File(File_A) and not End_Of_File(File_B) loop
  -- Process records from both files
  end loop;

  while not End_Of_File(File_A) loop
  -- Process tail of file A
  end loop;

  while not End_Of_File(File_B) loop
  -- Process tail of file B
  end loop;

-- 
   C++: The power, elegance and simplicity of a hand grenade.