# This file is part of ranger, the console file manager.
# License: GNU GPL version 3, see the file "AUTHORS" for details.
from __future__ import (absolute_import, division, print_function)
from collections import deque
def flatten(lst):
"""Flatten an iterable.
All contained tuples, lists, deques and sets are replaced by their
elements and flattened as well.
>>> l = [1, 2, [3, [4], [5, 6]], 7]
>>> list(flatten(l))
[1, 2, 3, 4, 5, 6, 7]
>>> list(flatten(()))
[]
"""
for elem in lst:
if isinstance(elem, (tuple, list, set, deque)):
for subelem in flatten(elem):
yield subelem
else:
yield elem
def unique(iterable):
"""Return an iterable of the same type which contains unique items.
This function assumes that:
type(iterable)(list(iterable)) == iterable
which is true for tuples, lists and deques (but not for strings)
>>> unique([1, 2, 3, 1, 2, 3, 4, 2, 3, 4, 1, 1, 2])
[1, 2, 3, 4]
>>> unique(('w', 't', 't', 'f', 't', 'w'))
('w', 't', 'f')
"""
already_seen = []
for item in iterable:
if item not in already_seen:
already_seen.append(item)
return type(iterable)(already_seen)
if __name__ == '__main__':
import doctest
import sys
sys.exit(doctest.testmod()[0])