On Sun, 26 Jun 2005 00:54:42 -0400, Bengt Richter wrote
(in article <[EMAIL PROTECTED]>):
> On Sat, 18 Jun 2005 03:52:28 -0400, Brian van den Broek
> <[EMAIL PROTECTED]> wrote:
> [...]
>>
>> Now, the same sort of behaviour where the "if type" testing has been
>> replaced with code more in keeping with the OOP approach:
>>
>>>>> class C(object):
>> ... def report(self):
>> ... print "Found a C"
>> ...
>>>>> class D(object):
>> ... def report(self):
>> ... print "Found a D"
>> ...
>>>>> c = C()
>>>>> d = D()
>>>>> for item in (c, d):
>> ... item.report()
>> ...
>> Found a C
>> Found a D
>>>>>
>>
>
> The OP might want to consider factoring report into a base class, e.g.,
>
> >>> class Base(object):
> ... def art_name(self):
> ... cname = type(self).__name__
> ... art = 'an'[:1+(cname.upper() in 'A E F H I L M N O R S X' or
> ... len(cname)>1 and cname.upper()[0] in 'AEIOU')]
> ... return art, cname
> ...
> >>> class A(Base): pass
> ...
> >>> class B(Base): pass
> ...
> >>> class F(Base): pass
> ...
> >>> class Foo(Base): pass
> ...
> >>> class U(Base): pass
> ...
> >>> class Uhuh(Base): pass
> ...
> >>> items = A(), B(), F(), Foo(), U(), Uhuh()
> >>> for item in items: print 'Found %s %s' % item.art_name()
> ...
> Found an A
> Found a B
> Found an F
> Found a Foo
> Found a U
> Found an Uhuh
>
> Returning info rather than printing to stdout allows you
> to access and use it differently, e.g.,
>
> >>> items[3].art_name()
> ('a', 'Foo')
> >>> items[3].art_name()[1]
> 'Foo'
>
> (Don't know if the a/an logic is really general ;-)
>
> Regards,
> Bengt Richter
>
Thanks Bengt,
I'm just in the middle of refactoring my perfectly good top down utility to
an OO approach. It's going to be a much more abstract and verbose animal,
but that's OK because it's a learning exercise. To make use of the
abstraction I'm providing for output options of either .csv or .html table,
and I was approaching such with a separate output base class. I don't have
the nuances of the language down yet, but you might say I'm taking an AO
approach to OO refactoring??? :~) Streatching it a bit probably in calling
processing and reporting the two main aspects of an AO approach, but it's fun
and keeps my head busy. I've got a trial mockup of my decision sequence
factory pattern working, so at least I'm making progress towards
incomprehensible abstraction :<)) To avoid duplication I'm using code
objects with my factory pattern to create applicable class methods for an
instance. Yea, I'm overdoing it, but as I said it's a learning exercise.
I'll study what you supplied in the morning to see if I understand. That and
continue putting up firewood for next winter - tiring work in the 90 degree
weather we're having in northern NE - especially at my age.
Thanks again,
Lee C
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