En Thu, 14 Jun 2007 18:45:08 -0300, Stephen R Laniel <[EMAIL PROTECTED]>
escribió:
> Reading the Python docs, it looks like string exceptions
> will be a DeprecationWarning in Python 2.5. Is there any way
> to make them so in 2.4? Now how about if I want to turn all
> DeprecationWarnings into compile-time errors? Is there some
> way to do this?
Yes, using the warnings module.
First thing is to start Python using the -Wd argument so you can see ALL
the warnings, even the supressed ones:
C:\temp>python24 -Wd
Then see what happens when you raise a string exception:
py> raise "Error"
__main__:1: PendingDeprecationWarning: raising a string exception is
deprecated
Traceback (most recent call last):
File "<stdin>", line 1, in ?
Error
Now we know it is a PendingDeprecationWarning, and the message says
"raising a string exception is deprecated"
With this information we can build a filter. Do this at startup of your
program:
from warnings import filterwarnings
filterwarnings(action="error", message="raising a string exception",
category=PendingDeprecationWarning)
Or maybe, place it in sitecustomize.py.
Or, start Python using -W:
C:\temp>python24 -W "error:raising a string
exception:PendingDeprecationWarning"
Python 2.4.4 (#71, Oct 18 2006, 08:34:43) [MSC v.1310 32 bit (Intel)] on
win32
Type "help", "copyright", "credits" or "license" for more information.
py> raise "Error"
Traceback (most recent call last):
File "<stdin>", line 1, in ?
File "c:\apps\python\lib\warnings.py", line 61, in warn
warn_explicit(message, category, filename, lineno, module, registry,
File "c:\apps\python\lib\warnings.py", line 96, in warn_explicit
PendingDeprecationWarning: raising a string exception is deprecated
(btw, the right format for the -W option isn't documented, or at least
I've been unable to find it; each time I want to use -W I have to reread
the warnings module source...)
> End goal being that string exceptions would cause
> compilation to fail. A few times now, I've found myself
> doing
>
> class SomeClass:
> """docstring"""
> pass
>
> raise SomeClass, "Some description"
>
> and I've gotten a weird compiler error about the constructor
> for SomeClass. I'd prefer it just to fail there and not let
> me raise an exception that isn't subclassed beneath
> Exception.
The compiler won't complain here - you will have to inspect the code (or
use a tool like pylint or pychecker). The easy fix is just inherit from
Exception.
--
Gabriel Genellina
--
http://mail.python.org/mailman/listinfo/python-list
