Movement.

demos/brz/Brzozowski.ml

@@ -140,11 +140,6 @@ end
 
 include R
 
-(* This makes it easy to define memoizing functions of type [regexp -> _]. *)
-
-module M =
-  Memoize.ForHashedType(R)
-
 (* -------------------------------------------------------------------------- *)
 
 (* The empty expression [0] is encoded as 0-ary disjunction. *)
@@ -187,6 +182,23 @@ let rec (@@) (e1 : regexp) (e2 : regexp) : regexp =
 
 (* -------------------------------------------------------------------------- *)
 
+(* Iteration. *)
+
+let star (e : regexp) : regexp =
+  match skeleton e with
+  | EEpsilon
+  | EStar _ ->
+      (* [epsilon*] is [epsilon]. *)
+      (* [e**] is [e*]. *)
+      e
+  | EDisj [] ->
+      (* [0*] is [epsilon]. *)
+      epsilon
+  | _ ->
+      make (EStar e)
+
+(* -------------------------------------------------------------------------- *)
+
 (* Disjunction. *)
 
 let universal e =
@@ -235,21 +247,6 @@ let (&&&) e1 e2 =
 
 (* -------------------------------------------------------------------------- *)
 
-(* Iteration. *)
-
-let star (e : regexp) : regexp =
-  match skeleton e with
-  | EEpsilon
-  | EStar _ ->
-      (* [epsilon*] is [epsilon]. *)
-      (* [e**] is [e*]. *)
-      e
-  | EDisj [] ->
-      (* [0*] is [epsilon]. *)
-      epsilon
-  | _ ->
-      make (EStar e)
-
 (* Negation. *)
 
 let neg (e : regexp) : regexp =
@@ -273,6 +270,9 @@ let neg (e : regexp) : regexp =
 
 (* We memoize this function. (This is optional.) *)
 
+module M =
+  Memoize.ForHashedType(R)
+
 let nullable : regexp -> bool =
   M.fix (fun nullable e ->
     match skeleton e with