Problem subclassing tuple

[Michele Simionato]

"John Wilson" <tug at wilson.co.uk> wrote in message news:<mailman.1051634628.4864.python-list at python.org>...
> <snip> I want an object which has all the characteristics of a tuple with
> additional methods.

What about this ?

class Holder(tuple):
    def additionalmethod(self):
        print "ciao ciao"

t=Holder((1,2))

print t #=> (1,2)

t.additionalmethod() #=> ciao ciao

If you want to avoid the parenthesis, here is the solution:

class Holder(tuple):
    def __new__(cls,*args):
        return tuple.__new__(cls,args)
    def additionalmethod(self):
        print "ciao ciao"

t=Holder(1,2)

print t # => (1,2)

t.additionalmethod() #=> ciao ciao

Easy, isn't it ?

                                        Michele