Added overloading example.

git-svn-id: https://swig.svn.sourceforge.net/svnroot/swig/trunk/SWIG@4487 626c5289-ae23-0410-ae9c-e8d60b6d4f22

Examples/ocaml/shapes/example_prog.ml

@@ -0,0 +1,44 @@
+(* example_prog.ml *)
+
+open Example ;;
+
+let side_length (ax,ay) (bx,by) =
+  sqrt (((bx -. ax) ** 2.0) +. ((by -. ay) ** 2.0)) ;;
+
+let triangle_area a_pt b_pt c_pt =
+  let a = (side_length a_pt b_pt) 
+  and b = (side_length b_pt c_pt)
+  and c = (side_length c_pt a_pt) in
+  let s = (a +. b +. c) /. 2.0 in
+    sqrt (s *. (s -. a) *. (s -. b) *. (s -. c)) ;;
+
+let point_in_triangle (pta,ptb,ptc) x y =
+  let delta = 0.0000001 in (* Error *)
+  let ptx = (x,y) in
+    begin
+      let a_area = triangle_area pta ptb ptx
+      and b_area = triangle_area ptb ptc ptx
+      and c_area = triangle_area ptc pta ptx
+      and x_area = triangle_area pta ptb ptc in
+      let result = (abs_float (a_area +. b_area +. c_area -. x_area)) < delta
+      in
+	result
+    end ;;
+
+let triangle_class pts ob meth args =
+  match meth with
+      "cover" ->
+	(match args with
+	     C_list [ x_arg ; y_arg ] ->
+	       C_bool (point_in_triangle 
+			 pts (get_float x_arg) (get_float y_arg))
+	   | _ -> raise (Failure "cover needs two double arguments."))
+    | _ -> (invoke ob) meth args ;;
+	       
+let triangle =
+  new_derived_object 
+    new_shape
+    (triangle_class ((0.0,0.0),(0.5,1.0),(1.0,0.0)))
+    C_void ;;
+
+let _ = _draw_shape_coverage (C_list [ triangle ; C_int 60 ; C_int 20 ]) ;;