Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Ben Finney <ben+python@benfinney.id.au>
Newsgroups: comp.lang.python
Subject: Re: Multiple inheritance, super() and changing signature
Date: Sat, 04 Jun 2016 06:19:15 +1000
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Xref: csiph.com comp.lang.python:109438

Nagy László Zsolt <gandalf@shopzeus.com> writes:

> Fortunately, I can change all of the classes, and extracting the
> common parameter into a common base class worked.

This is why Liskov's Substitution Principle is good: Thinking of it as a
law helps lead to better design.

In this case, the same parameter doing different things in different
sub-classes meant that instances of those sub-classes had difficulty
substituting for the superclass. Interrogating the design against the
LSP reveals that.

> Problem solved. Thank you for all your help!
> Cooperative classes are fantastic! :-)

I'm glad you discovered them :-)

-- 
 \       “Truth is stranger than fiction, but it is because fiction is |
  `\     obliged to stick to possibilities, truth isn't.” —Mark Twain, |
_o__)                                          _Following the Equator_ |
Ben Finney