[Tutor] Class definitions

[dn]

On 2/01/24 12:53, Alan Gauld via Tutor wrote:
> On 01/01/2024 22:05, dn via Tutor wrote:
>> Are you training folk, or requiring in Code Reviews, the use of
>> parentheses in stand-alone class definitions (or not)?
>>
> 
> I'm not quite sure who you are addressing here?

When helping folk start-out, the preference is to go with the one and 
only one way to do things.

Code Review is about (organisational) convention.


>> Accordingly, wondered if you feel there is virtue in writing class-names
>> without parentheses, and only moving to such syntax upon reaching more
>> advanced levels involving inheritance (and multiple-inheritance)?
> 
> My personal take is that it would have been consistent with
> Python's "explicit is better" approach if class definitions
> always required the parens with object where appropriate
> 
> class MyClass(object):
> 
> Even though it meant more typing.

A useful concept to understand - but often rather too theoretical for 
first-timers.

Which has been true only since 'new style types' were brought-in 
(somewhere back in the mists of Python 2.n history). Thus, one of 
several changes to the way we define custom-classes.


> But Guido obviously thought different and we are stuck with
> the definition structures. Since the idiomatic way of writing
> it is to omit the parens that's what I do and encourage others
> to do too. Idioms are powerful tools.

That's what I was wondering. Is there some authoritative statement for this?

OTOH it seems a little odd, that some classes are defined with 
parentheses and others not.

Hence the 'full' parentheses indicate a sub-class, whereas the 'empty' 
ones indicate a super-class or something that stands-alone and outside 
of any hierarchy.

Consulting PEP-008 (latest update, last month) there is considerable 
discussion about "Designing for Inheritance" (much of which curls the 
hair of SOLID OOP-ers) but no mention of parentheses (that I noticed). 
Although, the one code-example does feature the ubiquitous Cartesian 
Co-ordinate as "class Point:"!?

-- 
Regards,
=dn