[Mailman-Developers] Some issues with the CVS head

[Ross Boylan]

I just got the latest Mailman sources from CVS, and noticed a couple
of things.

1) Required Python Version

Some of the modules (e.g., DNS.py) require Python 2.2 (e.g., reference
to email modules).  Yet the readme says Python 2.1.3 or greater is
required.  The wiki
http://www.zope.org/Members/bwarsaw/MailmanDesignNotes/FrontPage says
Python 2.0 will be required.

This is of particular concern for me because I'm thinking of borrowing
some parts for a Zope product, and Zope 2.5 uses Python 2.1 and
reportedly will not work with 2.2.  This is, of course, not a good
reason for Mailman to stay on Python 2.1.

I'm aware of the ZMailman project and sent a message to their list.
However, what I'm doing probably goes in a different direction (I
really just want the Bounce handling).

2) Code Inconsistencies

Bouncer uses getBounceInfo.  MemberAdaptor implements this (as well as
OldMemberAdaptor), but MailingList doesn't inherit from it.  So it
looks as if everything is not quite hooked up yet.

3) A Stylistic Comment

I also find it a little weird to see base classes making calls to
methods that they don't define or inherit from, on the assumption that
they will be mixed into something that does define them.  It seems to
me if this could be avoided, or at least if the classes could inherit
from the classes with the relevant protocols, it would be cleaner.  A
lower tech approach would be to note the dependencies in class
comments.

But I think the inheritance might make the dependencies explicit while
still preserving the ability to factor out chunks of functionality.

4) A Little Python Question

Could anyone explain to me what this is doing? (e.g. from DNS.py)
    return filter(None, addrs)
There are several uses of this filter(None,..) idiom in the code.

The 2.0 code even says
    return filter(None, addrs) or None

The docs for filter say the first argument should be a function, which
None is not.  When I try it, it seems to be a noop (i.e., filter(None,
foo) == foo).  And or'ing with None (false) also seems pointless.