Newbie question: what's with "self"?

[Thomas Bartkus]

"donkeyboy" <fivenastydisco at hotmail.com> wrote in message
news:1155054411.511813.203270 at i42g2000cwa.googlegroups.com...
> This is probably a really basic question, but anyway ...
>
> I'm new to both Python and OO programming. From looking at a number of
> code examples, the word "self" is used a lot when referring to classes.
> As such, what does "self" mean and/or do? I've read things that say
> it's a naming convention, but no-one has really spelt it out (in idiot
> form!) in a way I can understand.
>
> Any help you can provide would be great: at the moment, when code
> doesn't work as expected, I'm randomly sprinkling "self"s in all over
> the place to see if that helps, but without much of an idea of what it
> really achieves.
>
> Thanks in advance!!
>

To put it simply, a class needs a way to know which instance (of itself!) to
operate on.

If you have a class "str" (and Python has that built in!), then there will
be many instances of class "str" in a typical program.  The parameter "self"
refers to the particular string the class method is being called to operate
upon.

If you have a method upper() that convert everything to uppercase, your
class definition would need the "self" parameter in order to know which
particular string to convert.

Thomas Bartkus