Re: Virtual functions are virtually invisible!

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From	Gregory Ewing <greg.ewing@canterbury.ac.nz>
Newsgroups	comp.lang.python
Subject	Re: Virtual functions are virtually invisible!
Date	Mon, 04 Jul 2011 20:43:35 +1200
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rantingrick wrote:
> what concerns me is the fact that virtual methods in derived
> classes just blend in to the crowd.

> I think we really need some
> sort of visual cue in the form of forced syntactical notation (just
> like the special method underscores).

If you're suggesting that it should be impossible to override
a method unless it is specially marked somehow in the base
class, I think that would be a bad idea.

One of the principles behind the design of Eiffel is that
classes should *always* be open to modification in any way
by a subclass. The reason is that the author of a class
library can't anticipate all the ways people might want to
use it. Consequently Eiffel has no equivalent of C++'s
"private" declaration -- everything is at most "protected".
It also has no equivalent of Java's "final".

I like the fact that Python doesn't have these either.

-- 
Greg

Thread

Virtual functions are virtually invisible! rantingrick <rantingrick@gmail.com> - 2011-07-03 15:55 -0700
  Re: Virtual functions are virtually invisible! Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2011-07-04 20:43 +1200
    Re: Virtual functions are virtually invisible! rantingrick <rantingrick@gmail.com> - 2011-07-10 10:15 -0700
      Re: Virtual functions are virtually invisible! Chris Angelico <rosuav@gmail.com> - 2011-07-11 03:30 +1000
      Re: Virtual functions are virtually invisible! Michael Hrivnak <mhrivnak@hrivnak.org> - 2011-07-10 20:31 -0400
        Re: Virtual functions are virtually invisible! rantingrick <rantingrick@gmail.com> - 2011-07-10 19:35 -0700
          Re: Virtual functions are virtually invisible! Michael Hrivnak <mhrivnak@hrivnak.org> - 2011-07-11 00:45 -0400
            Re: Virtual functions are virtually invisible! rantingrick <rantingrick@gmail.com> - 2011-07-11 06:42 -0700
              Re: Virtual functions are virtually invisible! Chris Angelico <rosuav@gmail.com> - 2011-07-12 00:41 +1000
                Re: Virtual functions are virtually invisible! rantingrick <rantingrick@gmail.com> - 2011-07-11 14:46 -0700
                Re: Virtual functions are virtually invisible! Chris Angelico <rosuav@gmail.com> - 2011-07-12 18:40 +1000
              Re: Virtual functions are virtually invisible! alex23 <wuwei23@gmail.com> - 2011-07-12 22:48 -0700
      Re: Virtual functions are virtually invisible! Fabio Zadrozny <fabiofz@gmail.com> - 2011-07-16 19:34 -0300
        Re: Virtual functions are virtually invisible! rantingrick <rantingrick@gmail.com> - 2011-07-16 15:58 -0700
          Re: Re: Virtual functions are virtually invisible! Dave Angel <d@davea.name> - 2011-07-16 21:45 -0400

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