Initial data commit

Task/Catamorphism/Ada/catamorphism.ada

@@ -0,0 +1,29 @@
+with Ada.Text_IO;
+
+procedure Catamorphism is
+
+   type Fun is access function (Left, Right: Natural) return Natural;
+   type Arr is array(Natural range <>) of Natural;
+
+   function Fold_Left (F: Fun; A: Arr) return Natural is
+      Result: Natural := A(A'First);
+   begin
+      for I in A'First+1 .. A'Last loop
+	 Result := F(Result, A(I));
+      end loop;
+      return Result;
+   end Fold_Left;
+
+   function Max (L, R: Natural) return Natural is (if L > R then L else R);
+   function Min (L, R: Natural) return Natural is (if L < R then L else R);
+   function Add (Left, Right: Natural) return Natural is (Left + Right);
+   function Mul (Left, Right: Natural) return Natural is (Left * Right);
+
+   package NIO is new Ada.Text_IO.Integer_IO(Natural);
+
+begin
+   NIO.Put(Fold_Left(Min'Access, (1,2,3,4)), Width => 3);
+   NIO.Put(Fold_Left(Max'Access, (1,2,3,4)), Width => 3);
+   NIO.Put(Fold_Left(Add'Access, (1,2,3,4)), Width => 3);
+   NIO.Put(Fold_Left(Mul'Access, (1,2,3,4)), Width => 3);
+end Catamorphism;