Need help with Python class idioms

[Josiah Carlson]

On 21 Jan 2004 12:43:28 -0800
tad at tadland.net (Tad Marko) wrote:

> Howdy!
> 
> I'm trying to get my head around Python and I've come to realize that
> there are a lot of idioms in Python that are a bit different than in
> other languages. I have a class similar to what I've included below.
> The only difference is that in the real class, I have even more
> mandatory attributes. Too many to specify at once on a constructor and
> they don't always exist at construction time anyway, so the accessor
> idiom must remain.
> 
> Can anyone suggest a more Pythony way to do the following?
> 
> Thanks,
> Tad
> 
> #!/bin/env python
> 
> class A:
>     def __init__(self):
>         self.mandatoryVar1 = None
>         self.mandatoryVar2 = None
> 
>     def setMV1(self, mv1):
>         self.mandatoryVar1 = mv1
> 
>     def setMV2(self, mv2):
>         self.mandatoryVar2 = mv2
> 
>     def saveToDB(self, db):
>         if self.mandatoryVar1 == None:
>             raise Exception, "Mandatory Var 1 not set."
>         if self.mandatoryVar2 == None:
>             raise Exception, "Mandatory Var 2 not set."
> 
>         # Using db, do whatever saving stuff is needed.


mandatoryvariables = dict(mandatoryvar1=mv1, mandatoryvar2=mv2...)
inst = A()
inst.__dict__.update(mandatoryvariables)

That should work for you.
 - Josiah