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From: mbk@inls1.ucsd.edu (Matt Kennel)
Newsgroups: comp.lang.ada
Subject: Re: Child packages [nn,pedo,incest,cons
Date: 16 Oct 1994 23:54:15 GMT
Organization: Institute For Nonlinear Science, UCSD
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References: <1994Oct14.121611.22416@sei.cmu.e>
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Date: 1994-10-16T23:54:15+00:00
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firth@sei.cmu.edu wrote:
: Subject: Child packages [nn,pedo,incest,cons]

: In article <1994Oct14.094121@di.epfl.ch> Robb.Nebbe@di.epfl.ch (Robb Nebbe) writes:

: >|>    The private part and body of any child can access the private part of
: >|>    its parent (and grandparent...).

: In principle, any mechanism that allows one to extend an abstraction
: also allows one to break it.  That's a hard choice for the language
: designer to make.

How?  You have an original thing A that is "not broken".

In most OO languages, you can make B which is "like A"
except for blah blah blah.  Of course, the new stuff that you
do might happen to "break" the original intent of A.

But if your original program used A, and just A, how could A now
be broken?

--
-Matt Kennel  		mbk@inls1.ucsd.edu
-Institute for Nonlinear Science, University of California, San Diego
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