1 files changed, 52 insertions, 0 deletions
diff --git a/src/GF/Data/Map.hs b/src/GF/Data/Map.hs
new file mode 100644
index 000000000..1adc0523a
--- /dev/null
+++ b/src/GF/Data/Map.hs
@@ -0,0 +1,52 @@
+{- 
+   **************************************************************
+   * Filename      : Map.hs                                     *
+   * Author        : Markus Forsberg                            *
+   *                 markus@cs.chalmers.se                      *
+   * Last Modified : 15 December, 2001                          *
+   * Lines         : 53                                         *
+   ************************************************************** 
+-}
+
+module Map 
+           (
+           Map,
+           empty,
+	   (!),     -- lookup operator.
+	   (!+),    -- lookupMany operator.
+	   (|->),   -- insert operator.
+	   (|->+),  -- insertMany operator.
+	   (<+>),   -- union operator.
+	   flatten  -- 
+	   ) where
+
+import RedBlack
+
+type Map key el = Tree key el
+
+infixl 6 |->
+infixl 6 |->+
+infixl 5 !
+infixl 5 !+
+infixl 4 <+>
+
+empty :: Map key el
+empty = emptyTree
+
+(!) :: Ord key => Map key el -> key -> Maybe el
+fm ! e = lookupTree e fm
+
+(!+) :: Ord key => Map key el -> [key] -> [Maybe el]
+fm !+    []  = []
+fm !+ (e:es) = (lookupTree e fm): (fm !+ es)
+
+(|->) :: Ord key => (key,el) -> Map key el -> Map key el
+(x,y) |-> fm = insertTree (x,y) fm
+
+(|->+) :: Ord key => [(key,el)] -> Map key el -> Map key el
+[]         |->+ fm = fm
+((x,y):xs) |->+ fm = xs |->+ (insertTree (x,y) fm)
+
+(<+>) :: Ord key => Map key el -> Map key el -> Map key el
+(<+>) fm1 fm2 =  xs |->+ fm2
+ where xs = flatten fm1