Nagy László Zsolt <gand...@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 -- https://mail.python.org/mailman/listinfo/python-list
