On May 30, 10:11 pm, theju <[EMAIL PROTECTED]> wrote:
> Hello all,
> I've two objects (both instances of a class called Person) and I want
> to use the __and__ method and print the combined attributes of the two
> instances.
>
> To be precise, here is my code....
>
> class Person:
> def __init__(self,name):
> self.name = name
> def print_name(self):
> print self.name
> def __and__(self,other):
> self.name = '%s AND %s' %(self.name,other.name)
> return self.name
>
> p = Person("John")
> q = Person("George")
>
> r = p and q
> print r.print_name()
Try:
class Person(object):
def __init__(self, name):
self.name = name
def __and__(self, other):
return '%s AND %s' % (self.name, other.name)
p = Person("John")
q = Person("George")
r = p & q
print r
(1) A "getter" method (like your print_name
method) is usually not needed, just access the
attribute of the instance. Like,
print p.name
(2) I doubt that you want the __and__ special
method to alter the name attribute of an
instance.
(3) You want to use the '&' operator
to dispatch to the __and__ method; __and__
is typically used for Numeric objects.
(4) You misunderstood how the 'and' operator
is used. The expression 'p and q' causes p to
be evaluated; if p is false, its value is returned;
otherwise q is evaluated and its value is returned.
--
Hope this helps,
Steven
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