trag1c

The best of rejected PEPs

A collection of my best findings when looking through rejected Python Enhancement Proposals (as of Jan 6, 2024).

PEP 204: Range Literals

(2000, Python 2.0)

>>> [1:10]
[1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> [:5]
[0, 1, 2, 3, 4]

trag1c

Based on the WordNet corpus, omitting results containing:

• slashes (e.g. lo/ovral)
• spaces (e.g. living_thing)
• digits (e.g. 1900s)

Generated with the following Python script using NLTK:

from pathlib import Path

from nltk.corpus import wordnet

trag1c

>>> try:
...     int("")
... except ValueError:
...     raise RuntimeError

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 10: ''

trag1c

When a function never returns anything (i.e. returns None), it doesn't require an explicit return at the end and early returns should be done without providing any value:

# Correct
def greet(name: str) -> None:
    print(f"Hello {name}!")


# Wrong

trag1c

Stuff Removed in Python 3.x

• Stuff Removed in Python 3.x
  • Python 3.0
    • C API
    • Modules
  • Python 3.2
    • C API
  • Python 3.3
• C API

trag1c

getattr(__builtins__,__file__.__getitem__((b:=(a:=(int().__pow__(int()))).__add__(a.__abs__()).__invert__()).__sub__(b).__add__(a.__invert__()))+getattr.__name__.__getitem__(int().__invert__())+__name__.strip(chr(b.__neg__().__pow__(-b).__mul__(b.__neg__()).__add__(b.__neg__().__mul__(b.__neg__())).__add__(b.__neg__()).__add__(b.__neg__()).__sub__(a))).__getitem__(b.__neg__().__sub__(a))+dir().__getitem__(float().__trunc__()).__getitem__(b.__neg__())+type.__class__.__class__.__class__.__class__.__class__.__class__.__class__.__class__.__name__.__getitem__(slice(None,a)))(object.__doc__[a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a+a]+license.__doc__[(a+a)**-b]+[*PermissionError.__doc__].pop(int()).lower()+str(__debug__)[~a]+type(complex()).__name__.__getitem__(~complex().real.__trunc__()))

trag1c

lambda LАMBDA=0xa,*,LАMBDА=[[0o1]],LAMBDА=~bool(),LAMВDA=None:(LAMВDА:=lambda *LАMВDA:([lambda:LАMBDА,lambda:LAMВDА((LАMВDА:=LАMBDА.__getitem__(LAMBDА).__getitem__(LAMBDА).__sub__(LAMBDА)),(LАMBDА.append([*(getattr(__builtins__,dir(__builtins__).__getitem__(getattr(__builtins__,(str.__name__.__getitem__(LAMBDА.__sub__(LAMBDА))).__add__((__import__("slootcnuf".__getitem__(slice(LAMВDA,LAMВDA,LAMBDА)))._HashedSeq.__base__.__name__).__getitem__(slice(LAMВDA,(LAMBDА.__sub__(LAMBDА)).__sub__(LAMBDА.__add__(LAMBDА))))).__add__(ChildProcessError.__name__.__getitem__(slice(((LAMBDА.__add__(LAMBDА)).__pow__((LAMBDА.__sub__(LAMBDА)).__sub__(LAMBDА.__add__(LAMBDА)))).__mul__((LAMBDА.__sub__(LAMBDА)).__sub__(LAMBDА.__add__(LAMBDА))),((LAMBDА.__add__(LAMBDА)).__pow__((LAMBDА.__sub__(LAMBDА)).__sub__(LAMBDА.__add__(LAMBDА)))).__mul__((LAMBDА.__sub__(LAMBDА)).__sub__(LAMBDА.__add__(LAMBDА))).__sub__(LAMBDА.__add__(LAMBDА))))))(LAMВDA,LAMВDA,LAMBDА)).__getitem__((LAMBDА.__add__(LAMBDА)).__pow__(LAMBDА.__sub__(LAMBDА).__sub__

trag1c

(lambda _____,___=(getattr(__builtins__,dir(__builtins__)[ord(dir(__builtins__)[(_______:=(________:=__import__('math').e).__floor__() .__add__(________.__ceil__()))][_______.__add__(int().__pow__(int()))]).__sub__(_______.__floordiv__(_______))])(~(int().__pow__(int())))):[_:=[lambda _:[__:=lambda _,____=(___.__pow__(___).__add__(___.__floordiv__(___))):[___.__floordiv__(___),[__,lambda _,__:___.__sub__(___)][_____.__mod__(____).__eq__(___.__sub__(___))or(_____.__mod__(____.__add__(___)).__eq__(___.__sub__(___)))](_____,____.__add__(___).__add__(___.__pow__(___)))][____.__pow__(___).__le__(_____)],lambda _:___.__sub__(___)][_____.__mod__(___).__eq__(___.__sub__(___))or(_____.__mod__(___.__add__(___.__floordiv__(___))).__eq__(___.__sub__(___)))](_____),lambda ______:______.__gt__(___.__floordiv__(___))][_____.__le__(___.__add__(___.__floordiv__(___)))](_____),___.__floordiv__(___)][_==getattr(__builtins__,dir(__builtins__)[___.__pow__(___.__mul__(___).__add__(___.__floordiv__(___))).__add__(___.__mul__(___)._

trag1c

getattr(__builtins__,dir(list)[-(_:=((int()**int())+(int()**int())))**_][int()]+(f"{RecursionError!r}")[::-False**False][_]+zip.__doc__[int(_*(_+(int()**int()/_)))]+getattr(int,dir(int)[(~_)**_])[_//_]+breakpoint.__name__[(_+_//_)**_])(dir(__builtins__)[ord(dir(quit)[_**_+_][~_])-_//_][int()]+iter.__init__.__init__.__str__()[_**_**_+_*_+_//_])