__slots__

[Georg Brandl]

Antoon Pardon wrote:
> Op 2006-03-25, John J. Lee schreef <jjl at pobox.com>:
>> aleaxit at yahoo.com (Alex Martelli) writes:
>> [...]
>>> you should be using pychecker or pylint
>> [...]
>>
>> I'm curious, as somebody who doesn't regularly use these tools: How do
>> they fit into your workflow?  Do you run them every few hours, every
>> day, every time you run functional tests, every release, every so
>> often, on gut feeling about when it's likely to catch problems...?
>>
>> How do you cope with spurious warnings?  Does it involve tweaking code
>> to quell warnings?  Keeping suppression lists?  Maintaining special
>> invocations of pychecker / pylint per-project?  Do they cope well with
>> other people's code who do not use these tools?
> 
> IMO they don't cope well unless you adapt to what they expect.
> 
> I just tested the two.
> 
> pylint gave me countless warnings because I use two space to indent
> instead of four. It also didn't like that I used uppercase letters
> in my identifiers. That there was no space after a comma or
> around an operator was a problem too.

Pylint knows different types of issues, these are "code style" issues
and can be
 - turned off
 - configured to what you like.
They help getting your coding style consistent and default to PEP8 style.

> That I use the same name for the index variable of for loops in
> different scopes is also warned about.

Well, everything that _could_ be problematic _or_ confuse a reader is
warned about. Pretty good in my eyes.

> Pychecker also warns about these shadowed variable. Pychecker
> goes even so far to warn you that a local variable in an imported
> module is shadowing a global variable of yours. Like the following
> line:
> 
> /usr/lib/python2.3/random.py:247: Local variable (i) shadows global
> defined on line 43 in file demo1a.py

That's odd. How are the two modules related?

> So it seems pychecker thinks I shouldn't use something like
> 
> for i in lst:
>   ...
> 
> in my code at the global level because some module in the standard
> library has a function with a local i.
> 
> Pychecker also froze on my system.

Pychecker imports the modules. Thus these things can happen when a
module expects not to be imported as-is.

> I don't recommend the use of these tools.

Well, then I don't recommend anyone reading your code <wink>

Georg