Improved multimethods.py

[David Mertz]

"Samuele Pedroni" <pedronis at bluewin.ch> wrote previously:
|I think a multi-argument generalization of super (similar also to
|Cecil resend), would be the most flexible, pythonic solution.

I'm actually still not convinced that using this is a good idea in
practice.  But then, I've come to believe that 'super()' cannot be
trusted either (even though I am starting to appreciate the elegance of
C3 linearization) *wink*.  Even though I've never really been a C++
programmer, I sense a virtue in explicitly naming the superclass you
want to call.

Nonetheless, I don't want to disappoint Sam and Paul, so I've added this
functionality to:

    http://www.gnosis.cx/secret/multimethods.py

I decided to call the capability 'dispatch.next_method()' rather than
'multi_super()' that I had toyed with.  This naming follows Dylan, and
would seem to serve the same purpose.

There are some more improvements too.  I gave an example of using
(simulated) positional and keyword arguments in multimethods.  I made
lexicographic_mro() the default linearization.

One thing I don't yet have is a linearization that matches Dylan, i.e.
rejecting ambiguities.  If anyone feels like contributing that, I'd be
thankful.

Yours, David...

--
mertz@  | The specter of free information is haunting the `Net!  All the
gnosis  | powers of IP- and crypto-tyranny have entered into an unholy
.cx     | alliance...ideas have nothing to lose but their chains.  Unite
        | against "intellectual property" and anti-privacy regimes!
-------------------------------------------------------------------------