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To: info-hol@cs.uidaho.edu
Subject: Re: Mutually recursive definitions
Cc: indra@cse.iitkgp.ernet.in
Date: Fri, 10 Jun 1994 13:57:29 +0200
From: schneide <schneide@ira.uka.de>
Message-Id: <"i80fs2.ira.686:10.05.94.11.57.55"@ira.uka.de>


Why not defining a global function evenoddlist that  subsumes 
evenlist and oddlist, i.e. 

evenoddlist even [] = even 
evenoddlist even (CONS h t) =(h => evenoddlist (~even) t | evenoddlist even t

After this you can define

evenlist l = evenoddlist T l
oddlist l = evenoddlist F l

I hope this could help,
Klaus.