added unique function, moved flatten to ext/iter_tools

1 files changed, 43 insertions, 0 deletions

diff --git a/ranger/ext/iter_tools.py b/ranger/ext/iter_tools.py
new file mode 100644
index 00000000..913b9c7d
--- /dev/null
+++ b/ranger/ext/iter_tools.py
@@ -0,0 +1,43 @@
+# Copyright (c) 2009, 2010 hut <hut@lavabit.com>
+#
+# Permission to use, copy, modify, and/or distribute this software for any
+# purpose with or without fee is hereby granted, provided that the above
+# copyright notice and this permission notice appear in all copies.
+#
+# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
+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.
+	"""
+	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)
+	"""
+	already_seen = []
+	for item in iterable:
+		if item not in already_seen:
+			already_seen.append(item)
+	return type(iterable)(already_seen)