1 files changed, 67 insertions, 0 deletions
diff --git a/ocaml-binary-annot/camlp4/examples/macros.ml b/ocaml-binary-annot/camlp4/examples/macros.ml
new file mode 100644
index 0000000000..fe7b7392ec
--- /dev/null
+++ b/ocaml-binary-annot/camlp4/examples/macros.ml
@@ -0,0 +1,67 @@
+open Camlp4.PreCast;;
+let foldr_funs = ref [];;
+let foldl_funs = ref [];;
+AstFilters.register_str_item_filter begin
+  Ast.map_expr begin function
+  | <:expr@loc< def_foldr $lid:name$ $e$ >> ->
+      foldr_funs := (name, e) :: !foldr_funs; <:expr@loc<()>>
+  | <:expr@loc< def_foldl $lid:name$ $e$ >> ->
+      foldl_funs := (name, e) :: !foldl_funs; <:expr@loc<()>>
+  | e -> e
+  end
+end#str_item;;
+AstFilters.register_str_item_filter begin
+  Ast.map_expr begin function
+  | <:expr@loc< $lid:name$($tup:e$) >> when List.mem_assoc name !foldl_funs ->
+      let op = List.assoc name !foldl_funs in
+      let rec foldl =
+        function
+        | [] -> assert false
+        | [x] -> x
+        | x :: xs -> <:expr@loc< $op$ $foldl xs$ $x$ >>
+      in foldl (List.rev (Ast.list_of_expr e []))
+  | <:expr@loc< $lid:name$($tup:e$) >> when List.mem_assoc name !foldr_funs ->
+      let op = List.assoc name !foldr_funs in
+      let rec foldr =
+        function
+        | [] -> assert false
+        | [x] -> x
+        | x :: xs -> <:expr@loc< $op$ $x$ $foldr xs$ >>
+      in foldr (Ast.list_of_expr e [])
+  | e -> e
+  end
+end#str_item;;
+(*
+
+AstFilters.register_str_item_filter begin
+  Ast.map_expr begin function
+  | <:expr@loc< foldl($lid:op$, $e$) >> ->
+      let rec foldl =
+        function
+        | [] -> assert false
+        | [x] -> x
+        | x :: xs -> <:expr@loc< $lid:op$ $foldl xs$ $x$ >>
+      in foldl (List.rev (Ast.list_of_expr e []))
+  | <:expr@loc< foldr($lid:op$, $e$) >> ->
+      let rec foldr =
+        function
+        | [] -> assert false
+        | [x] -> x
+        | x :: xs -> <:expr@loc< $lid:op$ $x$ $foldr xs$ >>
+      in foldr (Ast.list_of_expr e [])
+  | e -> e
+  end
+end#str_item;;
+
+AstFilters.register_str_item_filter begin
+  Ast.map_expr begin function
+  | <:expr@loc< \!+ ($tup:e$) >> ->
+      begin match Ast.list_of_expr e [] with
+      | [] | [_] -> assert false
+      | x :: xs -> List.fold_left (fun acc x -> <:expr@loc< $acc$ + $x$ >>) x xs
+      end
+  | <:expr< \!+ $e$ >> -> e
+  | e -> e
+  end
+end#str_item;;
+*)