OK, looking a bit deeper: In [69]: timedelta.__new__.__doc__ Out[69]: 'Create and return a new object. See help(type) for accurate signature.' In [70]: timedelta.__init__.__doc__ Out[70]: 'Initialize self. See help(type(self)) for accurate signature.' In [71]: timedelta.__doc__ Out[71]: 'Difference between two datetime values.' So the none of the docstrings have the proper information. And: help(timedelta) returns: Help on class timedelta in module datetime: class timedelta(builtins.object) | Difference between two datetime values. | | Methods defined here: | | __abs__(self, /) | abs(self) | | __add__(self, value, /) | Return self+value. .... So no signature either. I'm guessing this is because argument clinic has not been properly applied -- so Ihave a PR to work on. but where does help() get its info anyway? I always thought docstrings were supposed to be used for the basic, well, docs. And between the class and __new__ and __init__, somewhere in there you should learn how to initialize an instance, yes? -CHB On Mon, Jun 4, 2018 at 6:21 PM, Matthias Bussonnier < bussonniermatthias@gmail.com> wrote:
On Mon, 4 Jun 2018 at 17:29, Ivan Pozdeev via Python-Dev < python-dev@python.org> wrote:
On 05.06.2018 3:09, Matthias Bussonnier wrote:
This may even be a bug/feature of IPython,
I see that inspect.signature(timedelta) fails, so if timedelta? says Init signature: timedelta(self, /, *args, **kwargs) Then this may be some IPython internal logic. The timedelta class seem to use __new__ instead of __init__ (not sure why)
Because it's an immutable type.
Ah, yes, thanks.
and __new__ have a meaningful signature, So maybe we should fallback on that during signature inspection.
According to https://stackoverflow.com/questions/4374006/check-for- mutability-in-python , there are no reliable tests for mutability.
Sure, but we can test if the signature of __init__ is (self,/, *args, **kwargs), and if it is, it is useless we can attempt to get the signature from __new__ and show that instead. We do similar things for docstrings, if __init__ have no docstring we look at the class level docstring. -- M
_______________________________________________ Python-Dev mailing list Python-Dev@python.org https://mail.python.org/mailman/listinfo/python-dev Unsubscribe: https://mail.python.org/mailman/options/python-dev/ chris.barker%40noaa.gov
-- Christopher Barker, Ph.D. Oceanographer Emergency Response Division NOAA/NOS/OR&R (206) 526-6959 voice 7600 Sand Point Way NE (206) 526-6329 fax Seattle, WA 98115 (206) 526-6317 main reception Chris.Barker@noaa.gov