empty classes as c structs?

[Scott David Daniels]

Christopher J. Bottaro wrote:
> I find myself doing the following very often:
> 
> class Struct:
>         pass
> ...
> blah = Struct()
> blah.some_field = x
> blah.other_field = y
> ...
> 
> Is there a better way to do this?  Is this considered bad programming
> practice?  I don't like using tuples (or lists) because I'd rather use
> symbolic names, rather than numeric subscripts.  Also, I don't like having
> to declare the empty Struct class everytime I want to do this (which is
> very often).

I have a module of my own (data.py) that I use a lot. It contains:

class Data(object):
     def __init__(self, **initial):
         for name, val in initial.iteritems():
             setattr(self, name, val)

     def __repr__(self):
         names = sorted([name for name in dir(self)
                         if not name.startswith('_')],
                         key=lambda name: (name.lower(), name))
         return '%s(%s)' % (self.__class__.__name__, ', '.join([
                    '%s=%r' % (nm, getattr(self, nm)) for nm in names]))

The advantage is that I can see the value in the Data object simply
by printing the object.  I use it like:

     from data import Data

     blah = Data(some_field=3, other_field=13)
     ...
     blah.other_field = 23
     ...

--Scott David Daniels
Scott.Daniels at Acm.Org