Initial data commit

Task/Amb/Python/amb-5.py

@@ -0,0 +1,42 @@
+from itertools import chain
+
+
+# amb :: [a] -> (a -> [b]) -> [b]
+def amb(xs):
+    return lambda f: list(
+        chain.from_iterable(
+            map(f, xs)
+        )
+    )
+
+
+# when :: Bool -> [a] -> [a]
+def when(p):
+    return lambda xs: xs if p else []
+
+
+# TEST ----------------------------------------------------
+
+# joins :: String -> String -> Bool
+def joins(a, b):
+    return a[-1] == b[0]
+
+
+print (
+    amb(['the', 'that', 'a'])(
+        lambda w1: when(True)
+
+        (amb(['frog', 'elephant', 'thing'])
+         (lambda w2: when(joins(w1, w2))
+
+          (amb(['walked', 'treaded', 'grows'])
+           (lambda w3: when(joins(w2, w3))
+
+            (amb(['slowly', 'quickly'])
+             (lambda w4: when(joins(w3, w4))(
+
+                 [w1, w2, w3, w4]
+             ))))))
+         )
+    )
+)