How to restore a builtin when parameter has same name?

Question

I know you're "not supposed to" use builtin names as parameters for functions, but sometimes they make the most sense:

def foo(range=(4,5), type="round", len=2):

But if this has been done, and the range variable has been processed and is no longer needed, how do I get back to the builtin range and use it inside foo()?

del range doesn't restore the builtin:

UnboundLocalError: local variable 'range' referenced before assignment

Range of what? Range of response times? Range of fuel efficiencies? There should be something you can roll into the name to differentiate from the generic built-in. — TigerhawkT3, Jul 02 '15 at 04:44
@TigerhawkT3 range of foo, obviously. `foo(foo_range=(4,5))` would be redundant. :) — endolith, Jul 02 '15 at 14:04

score 4 · Accepted Answer · edited Jul 02 '15 at 05:29

4

For Python 2.x

import __builtin__
range = __builtin__.range

For Python 3.x

import builtins
range = builtins.range

edited Jul 02 '15 at 05:29

Jens

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answered Jul 02 '15 at 04:38

Ethan Furman

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score 3 · Answer 2 · answered Jul 02 '15 at 04:43

3

Also for both python versions, you can use __builtins__ without importing anything.

Example -

>>> def foo(range=(4,5)):
...     print(range)
...     range = __builtins__.range
...     print(range)
...
>>> foo()
(4, 5)
<class 'range'>

answered Jul 02 '15 at 04:43

Anand S Kumar

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these answers all say that you shouldn't do that: http://stackoverflow.com/q/11181519/125507 – endolith Jul 02 '15 at 14:03

How to restore a builtin when parameter has same name?

2 Answers2