add method xprod

README.md

@@ -514,7 +514,7 @@ R.values({'a': 1, 'b': 2}) # [1, 2]
 - [ ] whereEq
 - [ ] without
 - [ ] xor
-- [ ] xprod
+- [x] xprod
 - [ ] zip
 - [ ] zipObj
 - [ ] zipWith

ramda/__init__.py

@@ -89,3 +89,4 @@
 from .uniqWith import uniqWith
 from .useWith import useWith
 from .values import values
+from .xprod import xprod

ramda/xprod.py

@@ -0,0 +1,18 @@
+from .private._curry2 import _curry2
+
+
+def inner_xprod(a, b):
+  idx = 0
+  ilen = len(a)
+  jlen = len(b)
+  result = []
+  while idx < ilen:
+    j = 0
+    while j < jlen:
+      result.append([a[idx], b[j]])
+      j += 1
+    idx += 1
+  return result
+
+
+xprod = _curry2(inner_xprod)

test/test_xprod.py

@@ -0,0 +1,21 @@
+
+import unittest
+
+import ramda as R
+
+"""
+https://github.com/ramda/ramda/blob/master/test/xprod.js
+"""
+
+
+class TestXProd(unittest.TestCase):
+  def test_returns_an_empty_list_if_either_input_list_is_empty(self):
+    self.assertEqual([], R.xprod([], [1, 2, 3]))
+    self.assertEqual([], R.xprod([1, 2, 3], []))
+
+  def test_creates_the_collection_of_all_cross_product_pairs_of_its_parameters(self):
+    self.assertEqual([[1, 'a'], [1, 'b'], [1, 'c'], [2, 'a'], [2, 'b'], [2, 'c']], R.xprod([1, 2], ['a', 'b', 'c']))
+
+
+if __name__ == '__main__':
+  unittest.main()