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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Wed, 4 Jan 2012 13:34:23 -0700
Subject: Re: Typed python comparison / code analysis questions
To: Lucas Vickers <lucasvickers@gmail.com>
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On Wed, Jan 4, 2012 at 1:09 PM, Lucas Vickers <lucasvickers@gmail.com> wrot=
e:
> Hello,
>
> I'm relatively new to Python. =A0I come from C/C++ so I love the flexibil=
ity
> but I am slightly irked by the lack of compilation time checking.
>
> I've got two questions
> 1) Are there any tools that do an analysis of code and attempt to catch
> potential issues such as undefined variables, etc? =A0I use xdebug in php=
 for
> this purpose and it's a life saver. =A0Currently for Python I use module =
test
> cases and simulate situations but this doesn't catch everything and on a
> larger scale of development becomes difficult.

Yes, try pylint, pychecker, or pyflakes.



> 2) Is there a way to error when comparing variables of different types? =
=A0I
> was up late last night coding and caused a few bugs with the below code,
> which turns out to compare a type<str> to a type<int>. =A0I know good
> programming I should know what my variable types are, but it would be eve=
n
> better if I could always abide by a rule of using <_ (or something) which
> would spit an exception when comparing non-equal types/instances.

This is a well-known wart in Python 2.  The recommended solution would
be to upgrade to Python 3, which no longer allows ordered comparisons
between unrelated built-in types.

Cheers,
Ian