NetNews Usenet Archive 1992 #16/NN_1992_16.iso/spool/comp/object/3023

Internet Message Format | 1992-07-27 | 1.6 KB

Xref: sparky comp.object:3023 comp.lang.eiffel:990
Path: sparky!uunet!email!vexpert.dbai.tuwien.ac.at!mst
From: [e-mail] (Markus Stumptner)
Newsgroups: comp.object,comp.lang.eiffel
Subject: Re: Class methods (was: Re: How to design a data structure library)
Message-ID: <[e-mail]>
Date: 27 Jul 92 18:03:49 GMT
References: <[e-mail]>
Organization: DB and ES Subdivision, TU Vienna
Lines: 23

From article <[e-mail]>, by [e-mail] (Geoffrey Clemm):
> I believe you missed the central point of Richie's article, namely that
> Eiffel 3.0 has a clean way of handling this situation, to quote:

>>     !!c.union (a,b);

> With which I completely agree.  This avoids the unpleasant assymetry
> of c:=a.union(b).

I did get the point, I just don't like it.  I grant that the asymmetry
is avoided, but this is outwiehged by the fact that using the class
method is, in my opinion, a completely weird way of handling an
ordinary binary operator.  Sets are a bad example for that construct,
since they, as mathematical entities together with their appropriate
operators, should correspond fairly closely to, say, integers or
floats in this manner.  As an example, addition (which closely
corresponds to set union) is not a class message, and making it one
does not improve the clarity of the code.

--
Markus Stumptner                                [e-mail]
University of Technology Vienna                 vexpert![e-mail]
Paniglg. 16, A-1040 Vienna, Austria             ...mcsun!vexpert!mst