Gerard Flanagan wrote:
> I tried that Steve but it didn't work, and i don't think I can do what
> I want in any case. There is no method '__write' in the base class, it
> is only declared as an instance attribute in the constructor, like so:
>
> def __init__(self, file, encoding="us-ascii"):
> ...
> self.__write = file.write
> ...
>
> I tried putting '__write = None' at the class level (in the base class
> XMLWriter) but then, although '_XMLWriter__write' appears in
> 'dir(HtmlWriter)', I get 'NoneType is not callable'.
>
> I also tried 'def __write(self, text) : pass ' in the base class, but
> then the code runs but doesn't write the text I want - and anyway, if
> I'm going to change the base class, then i may as well just add the
> 'write_raw' method to the base directly!
>
> It's just some toy code at any rate, and I've learnt something new!
> Thanks for your reply.
>
> Gerard
>
Make sure you're calling the super's constructor before you try and access
the mangled member. Then (I forgot this part), you can just call the
mangled member from `self'. Example follows.
<foo.py>
class A(object):
def __init__(self):
self.__foo = lambda x, y : x + y
class B(A):
def __init__(self, x, y):
# Make sure you're calling the super's constructor first.
super(B, self).__init__()
self.sum = self._A__foo(x, y)
</foo.py>
>>> import foo
>>> b = foo.B(3, 4)
>>> b.sum
7
>>>
--
Steve Juranich
Tucson, AZ
USA
--
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