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Allow functools.reduces 'initial' to be a keyword argument #125916
Description
Feature or enhancement
Proposal:
functools.reduce takes function (generally a callable) and iterable, with an optional initial parameter:
https://docs.python.org/3/library/functools.html#functools.reduce
However, initial cannot be passed as a keyword argument, which reduces ;) readability,
from functools import reduce
from operator import sub
>>> reduce(sub, [1, 1, 2, 3, 5, 8], 21)
1
>>> reduce(sub, [1, 1, 2, 3, 5, 8], initial=21)
TypeError: reduce() takes no keyword argumentsAllowing initial as keyword argument will be more clear, and initial could also be passed as a keyword argument while making partial functions out of reduce.
Has this already been discussed elsewhere?
I have already discussed this feature proposal on Discourse
Links to previous discussion of this feature:
https://discuss.python.org/t/remove-positional-only-restriction-on-initial-parameter-of-reduce/68897
Activity
skirpichev commentedon Oct 24, 2024
See also #121677
skirpichev commentedon Oct 24, 2024
Also see #96640.
@sobolevn, did you actually try to do conversion and benchmark it?
pythongh-125916: convert reduce() to Argument Clinic
gh-125916: Adapt functools.reduce() to Argument Clinic (#125999)
gh-125916: Allow functools.reduce() 'initial' to be a keyword argument (
pythongh-125916: Adapt functools.reduce() to Argument Clinic (python#…
pythongh-125916: Allow functools.reduce() 'initial' to be a keyword a…
pythongh-125916: Adapt functools.reduce() to Argument Clinic (python#…
pythongh-125916: Allow functools.reduce() 'initial' to be a keyword a…
functools.reducedoes not accept keyword arguments for its parameters #139114 as a duplicate of this issue