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From: rick@tetrauk.UUCP (Rick Jones)
Newsgroups: comp.object
Subject: Re: Definition of 'reuse' (was Re: a real long title)
Keywords: reuse
Message-ID: <1194@tetrauk.UUCP>
Date: 20 Jun 91 08:18:13 GMT
References: <676362409.27@egsgate.FidoNet.Org> <1991Jun11.062703.15671@netcom.COM> <1991Jun14.103725.2765@dit.upm.es>
Reply-To: rick@tetrauk.UUCP (Rick Jones)
Organization: Tetra Ltd., Maidenhead, UK
Lines: 33

In article <1991Jun14.103725.2765@dit.upm.es> esink@turia.dit.upm.es (Eric Wayne Sink) writes:
>
>Anyone like to contribute their definition of 'software reuse' ?

Well, I can't come up with a slick definition off the cuff, but something I do
find curious, not to say irritating, is that a lot of Object Orients (is that a
word?) seem to think that OO technology has _invented_ reuse.  It may have
invented the word, but not the idea.

We've been _using_ function libraries in C, Fortran, etc. for years - only we
never said we were _reusing_ them.  What OO has done is to add some new
techniques for using the same code for multiple purposes.  I feel that the
whole reuse issue is getting rather over-rated at present.  OO doesn't solve
the problem of building general purpose libraries, on the contrary, it makes it
more difficult.  But if you get it right, then you've got something a lot more
powerful.

I get the impression that a lot of people are trying OO methods and languages
because they believe that reuse is the prime benefit - I think they are going
to be disappointed.  For me, the benfits are increased modularity,
encapsulation, and a more resilient structure.  If you manage those properly,
then you will be able to move on to effective reuse with the aid of experience,
but it doesn't come for free.

As a matter of interest, the most effective aspect of reuse for me in working
with Eiffel has been the existence of libraries of generic classes for data
structures.  This has been far more significant than inheritance as an aid to
productivity.
-- 
Rick Jones, Tetra Ltd.  Maidenhead, Berks, UK		rick@tetrauk.uucp
Chairman, NICE (Non-profit International Consortium for Eiffel)

Any fool can provide a solution - the problem is to understand the problem