Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!uunet!mcsun!corton!inria!uucp!adams
From: adams@aar.alcatel-alsthom.fr (Drew Adams)
Newsgroups: comp.software-eng
Subject: Re: Reusability considered harmful??(!!)
Message-ID: <1991Feb18.130036.3649@aar.alcatel-alsthom.fr>
Date: 18 Feb 91 13:00:36 GMT
References: <12385@pucc.Princeton.EDU> <7085@exodus.Eng.Sun.COM>
Reply-To: adams@zephir.UUCP (Drew Adams)
Organization: Alcatel Alsthom Recherche   (Marcoussis)
Lines: 28

In article <7085@exodus.Eng.Sun.COM> donm@margot.Eng.Sun.COM 
(Don Miller) writes:

>... treat code intended for reuse with great respect.  
>    This ... means focused functionality.
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>    Code which tries to be all things to all people is unlikely
>    to be really useful to anyone.

I agree 100%.  However, how are we then to interpret `functionality'?
Normally, one would expect  the term  to refer  to the  use(s) of the
thing  being  defined.    If  so,  then  isn't  this  an argument for
function-oriented,  as   opposed  to   object-  or  datatype-oriented
organization?  What, then, about  Bertrand Meyer's  argument (I don't
know  if  he  was the  first) that  function (use,  purpose) tends to
evolve more quickly than (abstract) data structure etc.?  

In  type-  or  object-orientation,  which  make  maximum  use of data
abstraction, the functionality, or use, of instances of  a given type
or class is part of its definition.  

Perhaps a loose interpretation  of `functionality'  should be assumed
here, that would also apply to objects.  Certainly `focussed' objects
and  datatypes  are to  be preferred  over those  that try  to be all
things to everyone.  
-- 
Drew ADAMS:     adams@aar.alcatel-alsthom.fr       Tel. +33 (1) 64.49.11.54 
            ALCATEL ALSTHOM Recherche, Route de Nozay, 91460 MARCOUSSIS, FRANCE