techsd
diff --git a/‎codext/binary/__init__.py‎
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diff --git a/‎codext/binary/rotate.py‎
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diff --git a/‎docs/enc/binary.md‎
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@@ -4,4 +4,5 @@
 from .excess3 import *
 from .gray import *
 from .manchester import *
+from .rotate import *
 
@@ -0,0 +1,52 @@
+# -*- coding: UTF-8 -*-
+"""Rotate-Bits Codec - rotate-N-bits content encoding.
+
+This codec:
+- en/decodes strings from str to str
+- en/decodes strings from bytes to bytes
+- decodes file content to str (read)
+- encodes file content from str to bytes (write)
+"""
+import operator
+
+from ..__common__ import *
+
+
+__examples__ = {
+    'enc(rotate-0|rotate-8|rotate-left-8)': None,
+    'enc(rotate1|rotate-right-1|rotate_1)': {'This is a test': "*449\x1049\x100\x10:29:"},
+    'dec(rotate1)':                         {'*449\x1049\x100\x10:29:': "Thhr hr ` tdrt"},
+    'enc(rotate-left-1|rotate_left_1)':     {'This is a test': "¨ÐÒæ@Òæ@Â@èÊæè"},
+}
+__guess__ = ["rotate-%s" % i for i in "12"] + ["rotate-left-%s" % i for i in "12"]
+
+
+if PY3:
+    def _getn(i):
+        m = 1
+        if str(i).startswith("left"):
+            i = i[4:].lstrip("-_")
+            m = -1
+        return m * int(i)
+
+
+    def _rotaten(text, n=1):
+        op = [operator.lshift, operator.rshift][n > 0]
+        n = abs(n)
+        return "".join(chr(op(ord(c), n)) for c in ensure_str(text))
+
+
+    def rotate_encode(i):
+        def encode(text, errors="strict"):
+            return _rotaten(text, _getn(i)), len(text)
+        return encode
+
+
+    def rotate_decode(i):
+        def decode(text, errors="strict"):
+            return _rotaten(text, -_getn(i)), len(text)
+        return decode
+
+
+    add("rotate", rotate_encode, rotate_decode, r"rotate(?:[-_]?bits)?[-_]?((?:left[-_]?)?[1-7])$")
+
@@ -139,3 +139,22 @@ This codec XORes each group of 4 bits of the input text with a 1-byte clock sign
 'This is a test!'
 ```
 
+-----
+
+### Rotate/Shift N bits
+
+This codec rotates N bits using the `>>` (to the right) and `<<` (to the left) operations.
+
+**Codec** | **Conversions** | **Aliases** | **Comment**
+:---: | :---: | --- | ---
+`rotate` | text <-> N-bits-rotated text | `rotate-N`, `rotate-right-N`, `rotate_left_N` | N belongs to [1,7] ; when nothing specified, it rotates to the right
+
+```python
+>>> codext.encode("test", "rotate-1")
+':29:'
+>>> codext.encode("test", "rotate_right-1")
+':29:'
+>>> codext.encode("test", "rotate_left_1")
+'èÊæè'
+```
+