Le 15 mars 2019 à 03:49:19, Steven D'Aprano
(st...@pearwood.info(mailto:st...@pearwood.info)) a écrit:
> On Wed, Mar 13, 2019 at 03:21:31AM -0700, Rémi Lapeyre wrote:
>
> > When __index__ is defined it means that there is a lossless conversion
> > to int possible. In this case, this means a
On Wed, Mar 13, 2019 at 03:21:31AM -0700, Rémi Lapeyre wrote:
> When __index__ is defined it means that there is a lossless conversion
> to int possible. In this case, this means a lossless conversion to
> float and complex is also possible
That's not correct:
py> n = 2**64 + 1
py> n ==
Le 22 février 2019 à 18:14:01, Nick Coghlan
(ncogh...@gmail.com(mailto:ncogh...@gmail.com)) a écrit:
> On Fri, 22 Feb 2019 at 18:29, Serhiy Storchaka wrote:
> > Should we add default implementations of __float__ and __complex__ when
> > either __index__ or __int__ is defined? Currently:
> >
> >
On Fri, 22 Feb 2019 at 18:29, Serhiy Storchaka wrote:
> Should we add default implementations of __float__ and __complex__ when
> either __index__ or __int__ is defined? Currently:
>
> >>> class A:
> ... def __int__(self): return 42
> ...
> >>> int(A())
> 42
> >>> float(A())
> Traceback
18.02.19 18:16, Rémi Lapeyre пише:
The documentation mentions at
https://docs.python.org/3/reference/datamodel.html#object.__index__
the need to always define both __index__ and __int__:
Note: In order to have a coherent integer type class, when
__index__() is defined __int__() should
Another point in favor of the change I just noticed is that int()
accept objects defining __index__ as its `base` argument:
Python 3.7.2 (default, Jan 13 2019, 12:50:01)
[Clang 10.0.0 (clang-1000.11.45.5)] on darwin
Type "help", "copyright", "credits" or "license" for more
On Tue, 19 Feb 2019 at 03:31, Rémi Lapeyre wrote:
> Nick Coghlan proposes to make __int__ defaults to __index__ when only the
> second
> is defined and asked to open a discussion on python-dev before making any
> change
> "as the closest equivalent we have to this right now is the "negative"
>
Hi, I open this thread to discuss the proposal by Nick Coghlan in
https://bugs.python.org/issue33039
to add __int__ and __trunc__ to a type when __index__ is defined.
Currently __int__ does not default to __index__ during class initialisation
so
both must be defined to get a coherant behavior:
