En Fri, 02 Feb 2007 15:30:53 -0300, Igor V. Rafienko <[EMAIL PROTECTED]>
escribió:
>> I was wondering whether it was possible to find out which parameter
> value is being used: the default argument or the user-supplied one.
> That is:
>
> def foo(x, y="bar"):
> # how to figure out whether the value of y is
> # the default argument, or user-supplied?
>
> foo(1, "bar") => user-supplied
> foo(1) => default
You can use None as a flag:
def foo(x, y=None):
if y is None: y="bar"
...
If None is valid, use your own flag:
_marker=object()
def foo(x, y=_marker):
if y is _marker: y="bar"
...
--
Gabriel Genellina
--
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