super question
Duncan Booth
duncan at NOSPAMrcp.co.uk
Tue Apr 8 11:38:48 EDT 2003
Lee Harr <missive at frontiernet.net> wrote in
news:WRBka.134$jS3.16 at news02.roc.ny.frontiernet.net:
> Should this be showing
> Af
> Bf
> ?
>
> How would I even get that output? I know I can do:
Try this:
>>> class A(object):
def f(self):
print 'Af'
if hasattr(super(A, self), 'f'):
super(A, self).f()
>>> class B(object):
def f(self):
print 'Bf'
if hasattr(super(B, self), 'f'):
super(B, self).f()
>>> class C(A,B):
def f(self):
print 'Cf'
super(C, self).f()
>>> c = C()
>>> c.f()
Cf
Af
Bf
>>> a = A()
>>> a.f()
Af
>>>
Note that A.f() calls B.f() if self is a C, but doesn't call anything if
self is an A.
Its easier if you want to propogate a function such as __init__ which you
know is in the base class, because then you don't have to check for
existence. Another way might be to define a class that is object with an
empty f and use that as the base for both A and B.
--
Duncan Booth duncan at rcp.co.uk
int month(char *p){return(124864/((p[0]+p[1]-p[2]&0x1f)+1)%12)["\5\x8\3"
"\6\7\xb\1\x9\xa\2\0\4"];} // Who said my code was obscure?
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