Oct. 7, 2020
3:43 p.m.
On Wed, Oct 7, 2020 at 12:41 AM Serhiy Storchaka <storchaka@gmail.com> wrote:
07.10.20 06:04, Guido van Rossum пише:
Ironically, complex numbers have a `__float__` method that always fails, and floats don't have a `__complex__` method but complex(x) succeeds if x is a float...
I wonder why not remove complex.__float__ (and complex.__int__, complex.__floordiv__, etc)?
Usability in a different context. ```
z = 1j float(z) Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: can't convert complex to float float(object()) Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: float() argument must be a string or a number, not 'object'
If float(z) gave the second error message it would be rather confusing,
since z is a number. I guess the alternative would be to explicitly check
for complex in float() when producing the error message. (Or phrase it as
"real number", which actually might work.)
I think you have pointed into a reasonable way forward -- make the types
match the intention of the protocols better.
I'm not sure what to do about Decimal though. I suspect we will end up
making changes to both the numbers and decimal modules.
--
--Guido van Rossum (python.org/~guido)
*Pronouns: he/him **(why is my pronoun here?)*
<http://feministing.com/2015/02/03/how-using-they-as-a-singular-pronoun-can-change-the-world/>