Mailman 3 October 2019 - Python-ideas

PEP's shouldn't require a sponsor
by Batuhan Taskaya Dec. 3, 2019

Dec. 3, 2019

Why do i need to convince a core developer for my PEP? AFAIK the steering council can include non core developers (i know it isn't that current case but for the future this is important). And if the last authority who will approve my PEP is the steering council i just need to convince them not core developers. Sponsors can stay (and they should because guidance is important) but thy shouldn't be mandatory. Let everyone to send their peps.

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Percent notation for array and string literals, similar to Perl, Ruby
by Steve Jorgensen Nov. 25, 2019

Nov. 25, 2019

See https://en.wikibooks.org/wiki/Ruby_Programming/Syntax/Literals#The_%_Notati… for what Ruby offers. For me, the arrays are the most useful aspect. %w{one two three} => ["one", "two", "three"] I did a search, and I don't see that this has been suggested before, but I might have missed something. I'm guessing I'm not the first person to ask whether this seems like a desirable feature to add to Python.

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Ability to set precedence of classdict (returned from __prepare__) for a metaclass type
by Steve Jorgensen Nov. 20, 2019

Nov. 20, 2019

When using a custom classdict to implement a DSL or use in the body of a class definition, from what I can tell by experiment, the classdict takes priority, and the surrounding context is only referenced if trying to get an item from the classdict raises `KeyError`. There is at least one case in which I would like to do the reverse, and have the classdict be secondary to (masked by) any variables defined in the context surrounding the execution of the class body. I have been able to at least … [View More]

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Please consider adding of functions file system operations to pathlib
by George Fischhof Nov. 16, 2019

Nov. 16, 2019

Good day all, as a continuation of thread "OS related file operations (copy, move, delete, rename...) should be placed into one module" https://mail.python.org/pipermail/python-ideas/2017-January/044217.html please consider making pathlib to a central file system module with putting file operations (copy, move, delete, rmtree etc) into pathlib. BR, George

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Make itertools recipes license easier
by Todd Nov. 11, 2019

Nov. 11, 2019

Per Guido's suggestion, I am starting a new thread on this. The itertools module documentation has a bunch of recipes that give various ways to combine the existing functions for useful tasks. [1] The issue is that these recipes are part of the documentation, and although IANAL, as far as I can tell this means they fall under the Python-2.0 license. [2] Normally using the Python-2.0 license is not a big deal because it is non-copyleft. You have to include the license text and explain what … [View More]

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foo.setParseAction(lambda a, b, c: raise FuckPython(":("))
by Soni L. Nov. 5, 2019

Nov. 5, 2019

foo.setParseAction(lambda a, b, c: raise FuckPython(":(")) is invalid syntax, which makes pyparsing useless.

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Python 4000: Have stringlike objects provide sequence views rather than being sequences
by Steve Jorgensen Nov. 3, 2019

Nov. 3, 2019

There are many cases in which it is awkward that testing whether an object is a sequence returns `True` for instances of of `str`, `bytes`, etc. This proposal is a serious breakage of backward compatibility, so would be something for Python 4.x, not 3.x. Instead of those objects _being_ sequences, have them provide views that are sequences using a method named something like `members` or `items`.

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Suggestion for behaviour change import mechanics
by Richard Vogel Oct. 31, 2019

Oct. 31, 2019

Hello everyone, I hope that E-Mail reaches someone. Since its the first time I am using a thing like a mailing list, I am saying sorry in advance for any inconvience caused ;-) However, I am writing you because of a small idea / feature request for the python import mechanism, which caused me some (in my opinion unnecessary) trouble yesterday: I noticed that when using an import statement, the following seems to be true: Current state: * Python will search for the first TOP-LEVEL hit … [View More]

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add a .with_stem() method to pathlib objects
by Ricky Teachey Oct. 30, 2019

Oct. 30, 2019

This is obviously a small thing, but it would be nice to be able to say: >>> Path(r"C:\x.txt").with_stem("y") WindowsPath('C:/y.txt') Rather than having to do some variation of: >>> old_path = Path(r"C:\x.txt") >>> old_path.with_name("y"+old_path.suffix) WindowsPath('C:/y.txt') Or: >>> old_path = Path(r"C:\x.txt") >>> old_path.with_name("y"+old_path.suffix) WindowsPath('C:/y.txt') Or (god forbid): >>> (old_path := Path(r"C:\x.txt")).… [View More]

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Ability to specify function for auto-test in Enum and pass the given value as an argument to _generate_next_value_
by Steve Jorgensen Oct. 28, 2019

Oct. 28, 2019

After messing around with `Enum` for a while, there's one small thing that I'd like to see improved. It seems limiting to me that the only way to trigger `_generate_next_value` is to pass `auto()`. What if, for a particular `Enum`, I would like to be able to use `()` as a shorthand for `auto()`? How about a more complex auto-generation that determines the final value based on both the given value and the name/key As an example of the second case, start with an `Enum` subclas in which each … [View More]

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