On Mon, 6 May 2019 19:39:39 +0300
Serge Matveenko <s@matveenko.ru> wrote:
> On Mon, May 6, 2019 at 7:29 PM Guido van Rossum <guido@python.org> wrote:
> >
> > On Mon, May 6, 2019 at 11:14 AM Serhiy Storchaka <storchaka@gmail.com> wrote: 
> >> I do not propose to change the current behavior. I propose to add new
> >> named constructors. In most cases default constructors can be used, but
> >> in cases when we use type check or different tricks to limit the type of
> >> the argument, we could use named constructors.
> >>
> >> Current named constructors:
> >>
> >> * dict.fromkeys()
> >> * int.from_bytes()
> >> * float.fromhex()
> >> * bytes.fromhex()
> >> * bytearray.fromhex() 
> >
> >
> > Understood. My point is that we won't be able to remove the original behavior, so we'd end up with two ways to do it. :-( 
>
> With all respect, I disagree. There are ways to evolve Python such as
> deprecation policies which proven to be effective. There are ways to
> monitor current features adoption on PyPI to see whether it is safe to
> remove deprecated things.

The main constructors for built-in types are used so pervasively that
there is no hope of actually removing such deprecated behavior.

'cpython-master/Lib/test/test_bytes.py' on line: 1023'

'cpython-master/Lib/test/test_bytes.py' on line: 1234'.

Currently, `bytes` is the most ambiguous resident in Python 3. It seems that in the final version (which is very different from the initial idea), it was created to surprise:
1. Those wishing to take it as a string in Python 2
2. Those who wish to perceive it as an array of integers from 0 to 255.
3. And those who want to see `bytes` as something else...

with kind regards,
-gdg