functools's partial and update_wrapper does not work together

[piotr.findeisen@gmail.com]

Hello!

I wanted to use a decorator to wrap partially applied function like
this:
from functools import *

def never_throw(f):
@wraps(f)
def wrapper(*args, **kwargs):
try: return f(*args, **kwargs)
except: pass
return wrapper

def foo(i):
raise ValueError(str( i) + " is too little")

never_throw(par tial(foo, 3))

However this fails with an exception saying
AttributeError: 'functools.part ial' object has no attribute
'__module__'.

How can I use generic wrapper (never_throw) around partials?

Thank you,
Piotr

[Bruno Desthuilliers]

Re: functools's partial and update_wrapper does not work together

piotr.findeisen @gmail.com a écrit :

Hello!
>
I wanted to use a decorator to wrap partially applied function like
this:
from functools import *
>
def never_throw(f):
@wraps(f)
def wrapper(*args, **kwargs):
try: return f(*args, **kwargs)
except: pass

Not an answer to your question, but: by all means, *never* use bare
except clauses. Please remember that SysExit and KeyboardInterru pt are
exceptions too.

return wrapper
>
def foo(i):
raise ValueError(str( i) + " is too little")
>
never_throw(par tial(foo, 3))
>
However this fails with an exception saying
AttributeError: 'functools.part ial' object has no attribute
'__module__'.
>
How can I use generic wrapper (never_throw) around partials?

If not already done by someone else, it might be worth filling a ticket
- generic decorators should work with any callable, not only with
functions (well, IMHO at least).

A possible workaround is:

_dont_pass = (
SysExit,
KeyboardInterru pt,
OtherStuffYouDo ntWantToPassSil entyHere,
)

def never_throw(f):
"""well... almost never..."
try:
f.__module__
except AttributeError:
f.__module__ = "whatever"
@wraps(f)
def wrapper(*args, **kwargs):
try:
return f(*args, **kwargs)
except Exception, e:
if isinstance(e, _dont_pass):
raise



HTH

[piotr.findeisen@gmail.com]

Re: functools's partial and update_wrapper does not work together

If not already done by someone else, it might be worth filling a ticket
- generic decorators should work with any callable, not only with
functions (well, IMHO at least).

you're right. it's already there http://bugs.python.org/issue3445

regards!