Re: Confused with methods

From: Matthias Kempka (lists_at_mkempka.de)
Date: 02/06/05 

Date: Sun, 06 Feb 2005 17:19:52 +0100
To: python-list@python.org

Hi Gerald,

When you define an instance method, the first parameter (in the
definition) represents the instance. By convention, you would name it
"self":

#####################
class B:
    def foo(self, x):
       print "we have two parameters: " + str(self) + " and " + x
#####################

then calling

######################
b = B()
b.foo("x")
######################

would be equivalent to

######################
b = B()
B.foo(b, "x")
######################

So, as you have noted, you need at least one parameter to attach the
method to an instance. This is because the instance _is_ the parameter.
Python does this for you internally.

For more documentation you should read the paragraph about classes in
the tutorial.

Regards,
Matthias

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