Merge pull request #32 from AKST/ord-instance

Ord instance

Author: paf31

README.md

@@ -28,6 +28,13 @@ instance showMap :: (Show k, Show v) => Show (Map k v)
 ```
 
 
+#### `ordMap`
+
+``` purescript
+instance ordMap :: (Ord k, Ord v) => Ord (Map k v)
+```
+
+
 #### `semigroupMap`
 
 ``` purescript

src/Data/Map.purs

@@ -46,6 +46,9 @@ instance eqMap :: (Eq k, Eq v) => Eq (Map k v) where
 instance showMap :: (Show k, Show v) => Show (Map k v) where
   show m = "fromList " ++ show (toList m)
 
+instance ordMap :: (Ord k, Ord v) => Ord (Map k v) where
+  compare m1 m2 = compare (toList m1) (toList m2)
+
 instance semigroupMap :: (Ord k) => Semigroup (Map k v) where
   (<>) = union