Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

OTOH daytaclass is a decorator for *better* metaclass compatibility. On Dec 10, 2017 13:17, "Antoine Pitrou" wrote: > On Sun, 10 Dec 2017 20:47:45 +0100 > Antoine Pitrou wrote: > > > Hi, > > > > On Sun, 10 Dec 2017 19:17:25 + > > Tin Tvrtković wrote: > > > Hello, > > > > > > I'm one of the

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

On Sun, 10 Dec 2017 20:47:45 +0100 Antoine Pitrou wrote: > Hi, > > On Sun, 10 Dec 2017 19:17:25 + > Tin Tvrtković wrote: > > Hello, > > > > I'm one of the attrs contributors, and the person who initially wrote the > > slots functionality there. > > > > We've given up on returning a new cl

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

Hi, On Sun, 10 Dec 2017 19:17:25 + Tin Tvrtković wrote: > Hello, > > I'm one of the attrs contributors, and the person who initially wrote the > slots functionality there. > > We've given up on returning a new class always since this can conflict with > certain metaclasses (have you notice

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

nto errors, so I'd welcome any development on this front. :) Date: Sat, 9 Dec 2017 08:52:15 -0500 > From: "Eric V. Smith" > To: Nathaniel Smith > Cc: Python Dev > Subject: Re: [Python-Dev] Issues with PEP 526 Variable Notation at the > class level > Messag

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

On 9 December 2017 at 12:14, Nathaniel Smith wrote: > You'd have to ask Hynek to get the full rationale, but I believe it was both > for consistency with slot classes, and for consistency with regular class > definition. For example, type.__new__ actually does different things > depending on wheth

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

I'm not a typing expert, but I want to second Raymond's concerns, and perhaps I'm qualified to do so as I gave the PyCon USA __slots__ talk this year and I have a highly voted answer describing them on Stack Overflow. Beautiful thing we're doing here with the dataclasses, by the way. I think ad

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

On 8 December 2017 at 19:28, Raymond Hettinger wrote: > > I'm hoping the typing experts will chime in here. The question is > straight-forward. Where should we look for the signature and docstring for > constructing instances? Should they be attached to the class, to > __init__(), or to __new_

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

On 12/8/2017 9:14 PM, Nathaniel Smith wrote: On Dec 7, 2017 12:49, "Eric V. Smith" > wrote: The reason I didn't include it (as @dataclass(slots=True)) is because it has to return a new class, and the rest of the dataclass features just modifies the given cl

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

On Dec 7, 2017 12:49, "Eric V. Smith" wrote: The reason I didn't include it (as @dataclass(slots=True)) is because it has to return a new class, and the rest of the dataclass features just modifies the given class in place. I wanted to maintain that conceptual simplicity. But this might be a reas

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

On Fri, Dec 8, 2017 at 3:44 PM, Eric V. Smith wrote: > On 12/8/2017 1:28 PM, Raymond Hettinger wrote: > >> >> >> On Dec 7, 2017, at 12:47 PM, Eric V. Smith wrote: >>> >>> On 12/7/17 3:27 PM, Raymond Hettinger wrote: >>> ... >>> >>> I'm looking for guidance or workarounds for two issues that have

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

On 12/8/2017 1:28 PM, Raymond Hettinger wrote: On Dec 7, 2017, at 12:47 PM, Eric V. Smith wrote: On 12/7/17 3:27 PM, Raymond Hettinger wrote: ... I'm looking for guidance or workarounds for two issues that have arisen. First, the use of default values seems to completely preclude the use

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

> On Dec 7, 2017, at 12:47 PM, Eric V. Smith wrote: > > On 12/7/17 3:27 PM, Raymond Hettinger wrote: > ... > >> I'm looking for guidance or workarounds for two issues that have arisen. >> >> First, the use of default values seems to completely preclude the use of >> __slots__. For example,

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

Yes, I think this is a reasonable argument for adding a 'slots' option (off by default) for @dataclass(). However I don't think we need to rush it in. I'm not very happy with the general idea of slots any more, and I think that it's probably being overused, and at the same time I expect that there

Re: [Python-Dev] Issues with PEP 526 Variable Notation at the class level

On 12/7/17 3:27 PM, Raymond Hettinger wrote: ... I'm looking for guidance or workarounds for two issues that have arisen. First, the use of default values seems to completely preclude the use of __slots__. For example, this raises a ValueError: class A: __slots__ = ['x', 'y']

[Python-Dev] Issues with PEP 526 Variable Notation at the class level

Both typing.NamedTuple and dataclasses.dataclass use the somewhat beautiful PEP 526 variable notations at the class level: @dataclasses.dataclass class Color: hue: int saturation: float lightness: float = 0.5 and class Color(typing.NamedTuple): hue: i