Why doesn't Pylint like built-in functions?

python list-comprehension pylint
igorgue picture igorgue · Aug 25, 2010 · Viewed 25.5k times · Source

I have a line like this:

filter(lambda x: x == 1, [1, 1, 2])

Pylint is showing a warning:

W:  3: Used builtin function 'filter'

Why is that? is a list comprehension the recommended method?

Of course I can rewrite this like this:

[x for x in [1, 1, 2] if x == 1]

And I get no warnings, but I was wondering if there's a PEP for this?

Answer

Ned Batchelder picture Ned Batchelder · Aug 25, 2010

Pylint often chatters on about stuff it shouldn't. You can disable the warning in a .pylintrc file.

This page http://pylint-messages.wikidot.com/messages:w0141 indicates the problem is that filter and map have been superseded by list comprehensions.

A line like this in your pylintrc file will quiet the warning:

disable=W0141

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