Guarding arithmetic

[Peter Otten]

Laszlo Nagy wrote:

>>>>> def safe(deferred, default=42, exception=Exception):
>> ...     try:
>> ...             return deferred()
>> ...     except exception:
>> ...             return default
> 
> What a beautiful solution! I was wondering if the following would be
> possible:
> 
> 
> def test(thing, default, *exc_classes):
>      try:
>          thing()
>      except *exc_classes:
>          return default
> 
> 
> But it is syntactically invalid.

The except clause allows a tuple of exceptions:

>>> def safe(deferred, default, *exceptions):
...     try:
...             return deferred()
...     except exceptions:
...             return default
... 
>>> safe(lambda: 1/0, -1, ValueError, ZeroDivisionError)
-1