Overload print

Alexander Kapps alex.kapps at web.de
Wed Aug 25 23:42:42 CEST 2010


Ross Williamson wrote:
> Hi All
> 
> Is there anyway in a class to overload the print function?

In Python <= 2.x "print" is a statement and thus can't be 
"overloaded". That's exactly the reason, why Python 3 has turned 
"print" into a function.

>>> class foo_class():
>>>     def __print__(self):
>>>           print "hello"
> 
>>> cc = foo_class()
>>> print cc
> 
> Gives:
> 
> hello

Hmm, on what Python version are you? To my knowledge there is no 
__print__ special method. Did you mean __str__ or __repr__ ?

> I'm looking at finding nice way to print variables in a class just by
> asking to print it

In Python3 you *can* overload print(), but still, you better define 
__str__() on your class to return a string, representing what ever 
you want:

In [11]: class Foo(object):
    ....:     def __str__(self):
    ....:         return "foo"
    ....:
    ....:

In [12]: f = Foo()

In [13]: print f
foo




More information about the Python-list mailing list