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functools's partial and update_wrapper does not work together

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(partial(foo, 3))

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

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

Thank you,
Piotr
Aug 21 '08 #1
2 2579
pi*************@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 KeyboardInterrupt are
exceptions too.
return wrapper

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

never_throw(partial(foo, 3))

However this fails with an exception saying
AttributeError: 'functools.partial' 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,
KeyboardInterrupt,
OtherStuffYouDontWantToPassSilentyHere,
)

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
Aug 21 '08 #2
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!
Aug 21 '08 #3

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