using "private" parameters as static storage?

[Arnaud Delobelle]

Aaron Brady <castironpi at gmail.com> writes:

> One way around it, which I like the idea of but I'll be honest, I've
> never used, is getting a function a 'self' parameter.  You could make
> it a dictionary or a blank container object, or just the function
> itself.
>
> @self_param
> def spam( self ):
>       self._count[0] += 1  #<--- how to initialize?
>       return "spam " * self._count[0]
>
> Only problem is, how do you initialize _count?
>
> Perhaps 'self_param' can take some initializers, and just initialize
> them off of **kwargs in the construction.
>
> @self_param( _count= [] )
> def spam( self ):
>       self._count[0] += 1
>       return "spam " * self._count[0]
>
> Looks really pretty (imo), but untested.

Rummaging through my ~/python/junk/ I found the almost exact same:

class NS(object):
    def __init__(self, dict):
        self.__dict__.update(dict)

def static(**vars):
    ns = NS(vars)
    def deco(f):
        return lambda *args, **kwargs: f(ns, *args, **kwargs)
    return deco

@static(ncalls=0, history=[])
def foo(ns, x):
   ns.ncalls += 1
   ns.history.append(x)
   print "Number of calls: %s\nHistory:%s" % (ns.ncalls, ns.history)

>>> foo(3)
Number of calls: 1
History:[3]
>>> foo(5)
Number of calls: 2
History:[3, 5]
>>> foo('spam')
Number of calls: 3
History:[3, 5, 'spam']
>>> 

-- 
Arnaud