[Python-Dev] reducing self.x=x; self.y=y; self.z=z boilerplate code

[Nick Coghlan]

Jp Calderone wrote:
> If you use vars(self).update(locals()), it even looks halfway
> pleasant ;)  I'm not sure what python-dev's current opinion of
> vars(obj) is though (I'm hoping someone'll tell me).
> 
> Of course, both of these fall over for __slots__'ful classes.  It'd
> be nice if there were a general way to deal with attributes of an
> instance, regardless of the implementation details of its memory
> layout.

That's where PJE's more generic approach comes in:

      def initialize(ob, args, excluded=['self']):
          for k in excluded:
              if k in args:
                  del args[k]
          for k, v in args.items():
              setattr(ob,k,v)

      class grouping:
          def __init__(self, x, y, z):
              initialize(self, locals())


Or, one could have a look at the 'namespace' module, which came out of 
the last pre-PEP covering this kind of area:

http://namespace.python-hosting.com/

'Record' is particularly interesting from an auto-initialisation point 
of view (the class attributes define the expected instance 
attributes). Although I may be a little biased, since I wrote that 
class. . .

Cheers,
Nick.

-- 
Nick Coghlan   |   ncoghlan at gmail.com   |   Brisbane, Australia
---------------------------------------------------------------
             http://boredomandlaziness.blogspot.com