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Subject: Re: Why do class methods always need 'self' as the first parameter?
From: Michiel Overtoom <motoom@xs4all.nl>
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Date: Thu, 1 Sep 2011 13:23:54 +0200
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> On Aug 31, 5:35 pm, "T. Goodchild" <tgoodch...@gmail.com> wrote:


>> So why is 'self' necessary on class methods?
>>=20
>> Just curious about the rationale behind this part of the language.

When instance variables are accessed with the 'self.varname' syntax, it =
is clear to the programmer that an instance variable is accessed, and =
not some global.  Other languages have weird syntax conventions like =
that you have to prepend all instance attributes with an '@', and in =
languages like C++ where there is not necessarily such a syntactic =
requirement, many programmers use ad-hoc constructs like '_varname' or =
'm_varname' to make the distinction clear.


>> It seems to me that the
>> most common practice is that class methods *almost always* operate on
>> the instance that called them.  It would make more sense to me if =
this
>> was assumed by default, and for "static" methods (methods that are
>> part of a class, but never associated with a specific instance) to be
>> labelled instead.

Yes, you have a point there. My personal preference would be to optimize =
for the most common case, while exceptions to the norm are still =
possible, but perhaps a bit more verbose.

Greetings

--=20
"Learn to value yourself, which means: fight for your happiness."  - Ayn =
Rand     =20