Here is the code:
class Dummy(object):
def __init__(self, v):
self.ticker = v
def main():
def _assign_custom_str(x):
def _s
Magic methods are only guaranteed to work if they're defined on the type rather than on the object.
For example:
def _assign_custom_str(x):
def _show_ticker(self):
return self.ticker
x.__class__.__str__ = _show_ticker
x.__class__.__repr__ = _show_ticker
return x
But note that will affect all Dummy
objects, not just the one you're using to access the class.
if you want to custmize __str__
for every instance, you can call another method _str in __str__
, and custmize _str:
class Dummy(object):
def __init__(self, v):
self.ticker = v
def __str__(self):
return self._str()
def _str(self):
return super(Dummy, self).__str__()
def main():
a1 = Dummy(1)
a2 = Dummy(2)
a1._str = lambda self=a1:"a1: %d" % self.ticker
a2._str = lambda self=a2:"a2: %d" % self.ticker
print a1
print a2
a1.ticker = 100
print a1
main()
the output is :
a1: 1
a2: 2
a1: 100