On 1/11/2016 6:26 PM, Skip Montanaro wrote:
Here's a dumb little bit of code, adapted from a slightly larger script:

#!/usr/bin/env python

"dummy"

import glob
import os

def compare_prices(*_args):
     "dummy"
     return set()

def find_problems(cx1, cx2, cx3, prob_dates):
     "dummy"
     for fff in sorted(glob.glob("/path/to/*.nrm")):
         sym = os.path.splitext(os.path.basename(fff))[0]
         prob_dates |= compare_prices("E:%s"%sym, cx1, cx2, cx3)

When I run pylint against it, it complains:

junk.py:10: [W0613(unused-argument), find_problems] Unused argument 'prob_dates'

I must be misunderstanding something about the |= operator as applied
to sets. If I read the docs correctly, s1 |= s2 is equivalent to
s1.update(s2). A dumb "test" at the prompt suggests that's true:

s1 = set("abc")
s2 = set("cde")
s1 | s2
set(['a', 'c', 'b', 'e', 'd'])
s1 |= s2
s1
set(['a', 'c', 'b', 'e', 'd'])
s1 = set("abc")
s1.update(s2)
s1
set(['a', 'c', 'b', 'e', 'd'])

If I change the last line of find_problems to call
prob_dates.update(), the message disappears. Why is pylint (1.4.2 BTW)
complaining that the prob_dates argument of find_problems is unused
when I use the |= operator?

A bug in pylint. It should treat both cases the same.


--
Terry Jan Reedy

--
https://mail.python.org/mailman/listinfo/python-list

Reply via email to