On 05.06.2018 17:56, Chris Barker wrote:
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?
In [5]: print(str.__doc__) str(object='') -> str str(bytes_or_buffer[, encoding[, errors]]) -> str Create a new string object from the given object. If encoding or errors is specified <...> As you can see, the start of the type's docstring contains constructor signature(s). Timedelta's one should probably do the same.
-CHB
On Mon, Jun 4, 2018 at 6:21 PM, Matthias Bussonnier <bussonniermatthias@gmail.com <mailto:bussonniermatthias@gmail.com>> wrote:
On Mon, 4 Jun 2018 at 17:29, Ivan Pozdeev via Python-Dev <python-dev@python.org <mailto: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 <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 <mailto:Python-Dev@python.org> https://mail.python.org/mailman/listinfo/python-dev <https://mail.python.org/mailman/listinfo/python-dev> Unsubscribe: https://mail.python.org/mailman/options/python-dev/chris.barker%40noaa.gov <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 <mailto:Chris.Barker@noaa.gov>
-- Regards, Ivan