Remove multiple inheritance in Python 3000

[GD]

Please remove ability to multiple inheritance in Python 3000.

Multiple inheritance is bad for design, rarely used and contains many
problems for usual users.

Every program can be designed only with single inheritance.

I also published this request at http://bugs.python.org/issue2667

[Stefan Behnel]

GD wrote:

Please remove ability to multiple inheritance in Python 3000.

I'm so happy *that's* a dead parrot, all right.

Stefan

[Diez B. Roggisch]

GD schrieb:

Please remove ability to multiple inheritance in Python 3000.

Multiple inheritance is bad for design, rarely used and contains many
problems for usual users.

Every program can be designed only with single inheritance.

Yes, sure. And that's why Java grew interfaces & it's class-diagrams are
hilariously complex. Because using single inheritance is so much better.

Diez

[Stefan Behnel]

GD wrote:

Please remove ability to multiple inheritance in Python 3000.

Multiple inheritance is bad for design, rarely used and contains many
problems for usual users.

Ah, one more:

"doctor, when I do this, it hurts!"

- "then don't do that!"

Stefan

[=?iso-8859-2?q?Cezary_Krzy=BFanowski?=]

Dnia Tue, 22 Apr 2008 04:07:01 -0700, GD napisa³(a):

Please remove ability to multiple inheritance in Python 3000.

Please send me 1 mln $.

I've always wanted to be rich and furthermore, I've got a lot of plans and
ideas how to spend that cash.

I also published this request at http://bugs.python.org/issue2667

I'll be not publishing the bug, as I don't want to leave trace, so that I
don't have to pay taxes.

With regards,
Cz@rny

[Bruno Desthuilliers]

GD a écrit :

Please remove ability to multiple inheritance in Python 3000.

Please dont.

Multiple inheritance is bad for design, rarely used and contains many
problems for usual users.

Don't blame the tool for your unability to use it properly.

Every program can be designed only with single inheritance.

Every program can be implemented in machine code.

[Carl Banks]

On Apr 22, 7:30 am, "Diez B. Roggisch" <de...@nospam.w eb.dewrote:

GD schrieb:

Please remove ability to multiple inheritance in Python 3000.

Multiple inheritance is bad for design, rarely used and contains many
problems for usual users.

Every program can be designed only with single inheritance.

Yes, sure. And that's why Java grew interfaces & it's class-diagrams are
hilariously complex. Because using single inheritance is so much better.

I have a couple issues with this, though I wholeheartedly agree with
the sentiment:

1. Java didn't grow interfaces, they were there from the start.

2. Java interfaces solve a different problem than MI (used properly)
does: interfaces are there to make types polymorphic, whereas
inheritance's main use is to share behavior.
Too many people believe polymorphism is the only noble goal of OO. If
that were true, there'd be no reason for multiple inheritance, or
single inheritance for that matter. But in my opinion, minimizing
code redundancy by allowing classes to share behaviors is far more
useful and important. That's why I wholeheartedly favor MI: it allows
classes to share behavior with restraints.

Java (for example) allows a class to share behavior with only one
other class, and that *severely* limits the opportunities to minimize
redundancy.
Carl Banks

[George Sakkis]

On Apr 22, 10:22*am, Carl Banks <pavlovevide... @gmail.comwrote :

Java (for example) allows a class to share behavior with only one
other class, and that *severely* limits the opportunities to minimize
redundancy.

Not really; composition is usually a better way to share functionality
and reduce redundancy than inheritance.

George

[Carl Banks]

On Apr 22, 10:36 am, George Sakkis <george.sak...@ gmail.comwrote:

On Apr 22, 10:22 am, Carl Banks <pavlovevide... @gmail.comwrote :

Java (for example) allows a class to share behavior with only one
other class, and that *severely* limits the opportunities to minimize
redundancy.

Not really; composition is usually a better way to share functionality
and reduce redundancy than inheritance.

I should have known this was coming. I disagree: inheritance is a
much better way to share behavior. Use inheritance by default,
composition if you have to. (Or composition when it actually reflects
a composition relationship, and not mere behavior sharing.)

With composition you're burdening the user with having to learn the
shared relationships that ought to be implementation details of the
class. E.g.,

obj.action_styl e.perform_actio n()

With inheritance, the user doesn't have to worry about these
relationships.

obj.perform_act ion()

It's better to isolate complexity (which inheritance does) than to
spread it out (which composition does).
Carl Banks

[Diez B. Roggisch]

I have a couple issues with this, though I wholeheartedly agree with

the sentiment:

1. Java didn't grow interfaces, they were there from the start.

I might have expressed myself wrong here - I should have written "needed
to introduce interfaces (right from the start)"

2. Java interfaces solve a different problem than MI (used properly)
does: interfaces are there to make types polymorphic, whereas
inheritance's main use is to share behavior.

But the *goal* of the polymorphy is mainly to have shared behavior. And
matter of factly e.g. in swing, you use inner classes that implement
most of the behavior you want, and override the few points where you
want differences - and then clumsily delegate to that inner class all
your interface-methods.

Diez