arguments of a function/metaclass

[goodwolf]

rubbishemail at web.de je napisao/la:
> Hello,
>
>
> I have a member function with many (20) named arguments
>
> def __init__(self,a=1,b=2):
>     self.a=a
>     self.b=b
>
> I would like to get rid of the many redundant lines like self.a=a and
> set the members automatically.
> The list of default arguments could be given like
>
> def __init__(**kwargs):
>     arglist={"a":1,"b":2]
>
> if this makes things easier
>
> Of course there has to be a check that raises an error in case of an
> unknown argument not mentioned in this list.
>
>
> I am sure there is an elegant way how to do this, could you give me any
> hints???
>
>
> Many thanks
>
>
>
> Daniel

def changeattrs(obj, __dict, **kwargs):
    for name, value in __dict.iteritems():
        if hasattr(obj, name):
            setattr(obj, name, value)
        else:
            raise AttributeError
    for name in kwargs:
        if hasattr(obj, name):
            setattr(obj, name, kwargs[name])
        else:
            raise AttributeError


def locals2self(depth=0):
    import sys
    ns = sys._getframe(depth+1).f_locals
    obj = ns['self']
    for name, value in ns.iteritems():
        if name != 'self':
            setattr(obj, name, value)





class C1(object):
    def __init__(self, a=1, b=2, c=3, d=4):
        locals2self()



class C2(object):
    a = 1
    b = 2
    c = 3
    d = 4
    
    def __init__(self, **kwargs):
        changeattrs(self, kwargs)