From 42e5b4cc8b2dbd76ba4567b73967de974831c666 Mon Sep 17 00:00:00 2001
From: Michael Orlitzky <michael@orlitzky.com>
Date: Thu, 1 Sep 2011 12:58:37 -0400
Subject: [PATCH] Add the 'disjoint' function.

---
 src/Misc.hs | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/Misc.hs b/src/Misc.hs
index 9dcbac9..b9220cb 100644
--- a/src/Misc.hs
+++ b/src/Misc.hs
@@ -3,6 +3,8 @@
 module Misc
 where
 
+import Data.List (intersect)
+
 
 -- | The standard factorial function. See
 --   <http://www.willamette.edu/~fruehr/haskell/evolution.html> for
@@ -57,3 +59,19 @@ all_equal xs =
     where
       first_element  = head xs
       other_elements = tail xs
+
+
+-- | Returns 'True' if the lists xs and ys are disjoint, 'False'
+--   otherwise.
+--
+--   Examples:
+--
+--   >>> disjoint [1,2,3] [4,5,6]
+--   True
+--
+--   >>>  disjoint [1,2,3] [3,4,5]
+--   False
+--
+disjoint :: (Eq a) => [a] -> [a] -> Bool
+disjoint xs ys =
+    intersect xs ys == []
-- 
2.43.2