PEP 318

John Roth newsgroups at jhrothjr.com
Mon Mar 22 14:37:46 CET 2004


"Jacek Generowicz" <jacek.generowicz at cern.ch> wrote in message
news:tyfisgx6wfo.fsf at pcepsft001.cern.ch...
> Nicolas Fleury <nid_oizo at yahoo.com_removethe_> writes:
>
> > I've given some Python courses, and the first reaction when showing
> > a class with some methods is something like "so I guess when the
> > first parameter is not named 'self' it makes a class method?".
>
> Just as a point of information:
>
> I teach Python courses ... hands-on interactive style ... class size =
> 12 ... I've given 8 of these so far ... I have _never_ had this
> reaction. (80% of the students have previous C++ and/or Java
> experience, and usually someone asks "How do I do class/static
> methods?".)
>
> Maybe the reason nobody believes this is because, fairly early on in
> the treatment of classes, I point out that there is nothing special
> about the name "self", but I usually ask the students what they make
> of it, before offering any of my own comments.

Excellent class design! When I was doing classes, I found
one of the most important questions I could ask myself in
the after-the-class analysis was "what could I have said
earlier that would have dealt with this question / confusion?"

> > If easing the creation of class methods is so important, I would
> > prefer a more radical approach with a end result that would be more
> > intuitive to newcomers:
>
> While I agree that there is a lot to be said for Python being guided
> by the principle of least surprise, I would argue against letting
> Python be shaped by the expectations of people whose expectations have
> been moulded by Java and C++, as those expectations are typically
> fundamentally flawed, and certainly inappropriate to Python. (For
> example, most (Java and C++ people, and hence generally most) people
> expect there to be access control, and hundreds of getters and setters
> all over the place. We do _not_ want this in Python. Etc., etc..
>
> > - Give a warning for all methods with first parameter not named "self"
> > in next versions of Python.
>
> That would be acceptable ...

Only if the intention is to move to making it a built-in. Otherwise there
really are people who use some other name than self (usually to save
keystrokes.)

> > - In a future major version of Python, 3 or 4, self becomes a keyword
> > and a first parameter named otherwise implies a class method (I
> > understand it could mean a lot of changes in code not using self).
>
> ... that would (IMHO) not.

John Roth





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