add method modulo

README.md

@@ -304,7 +304,18 @@ R.Min('A', None) # 'A', 'A' < 'None'
 - [ ] minBy
 - [ ] modify
 - [ ] modifyPath
-- [ ] modulo
+- [x] modulo
+
+Python modulo on negative numbers has different behavior than JS.
+
+```python
+5 % -3 # -1
+```
+
+```js
+5 % -3 // 2
+```
+
 - [ ] move
 - [x] 0.1.2 multiply
 - [ ] nAry

ramda/__init__.py

@@ -48,6 +48,7 @@
 from .match import match
 from .Max import Max
 from .Min import Min
+from .modulo import modulo
 from .multiply import multiply
 from .Not import Not
 from .nth import nth

ramda/modulo.py

@@ -0,0 +1,3 @@
+from .private._curry2 import _curry2
+
+modulo = _curry2(lambda x, y: x % y)

test/test_modulo.py

@@ -0,0 +1,22 @@
+
+import unittest
+
+import ramda as R
+
+"""
+https://github.com/ramda/ramda/blob/master/test/modulo.js
+"""
+
+
+class TestModulo(unittest.TestCase):
+  def test_divedes_the_first_param_by_the_second_and_returns_the_remainder(self):
+    self.assertEqual(0, R.modulo(100, 2))
+    self.assertEqual(1, R.modulo(100, 3))
+    self.assertEqual(15, R.modulo(100, 17))
+
+  def test_preserves_python_style_modulo_evaluation_for_negative_numbers(self):
+    self.assertEqual(3, R.modulo(-5, 4))
+
+
+if __name__ == '__main__':
+  unittest.main()