Remove the duplicate function [addl] in [Slr] and [Lr1]. Replace it with [Lr0.add_reductions].

src/lr0.ml

@@ -606,3 +606,27 @@ let restrict toks (k, toksr) =
   k, Array.map (fun toksri ->
     TerminalSet.inter toksri toks
   ) toksr
+
+(* A (state-local, possibly nondeterministic) reduction table maps
+   terminal symbols to lists of productions. *)
+
+type reductions =
+  Production.index list TerminalMap.t
+
+(* [add_reduction prod tok reductions] adds a reduction of [prod] on [tok]
+   to the table [reductions]. *)
+
+let add_reduction prod tok reductions =
+  let prods =
+    try
+      TerminalMap.lookup tok reductions
+    with Not_found ->
+      []
+  in
+  TerminalMap.add tok (prod :: prods) reductions
+
+(* [add_reductions prod toks reductions] adds a reduction of [prod] on every
+   token in the set [toks] to the table [reductions]. *)
+
+let add_reductions prod toks reductions =
+  TerminalSet.fold (add_reduction prod) toks reductions

src/lr0.mli

@@ -139,3 +139,19 @@ val restrict: TerminalSet.t -> lr1state -> lr1state
 val print_concrete: string -> concretelr1state -> string
 val print:          string ->         lr1state -> string
 val print_closure:  string ->         lr1state -> string
+
+(* A (state-local, possibly nondeterministic) reduction table maps
+   terminal symbols to lists of productions. *)
+
+type reductions =
+  Production.index list TerminalMap.t
+
+(* [add_reduction prod tok reductions] adds a reduction of [prod] on [tok]
+   to the table [reductions]. *)
+
+val add_reduction: Production.index -> Terminal.t -> reductions -> reductions
+
+(* [add_reductions prod toks reductions] adds a reduction of [prod] on every
+   token in the set [toks] to the table [reductions]. *)
+
+val add_reductions: Production.index -> TerminalSet.t -> reductions -> reductions

src/lr1.ml

@@ -509,18 +509,6 @@ let () =
       num := number + 1;
       node.number <- number;
 
-      (* Insertion of a new reduce action into the table of reductions. *)
-
-      let addl prod tok reductions =
-        let prods =
-          try
-            TerminalMap.lookup tok reductions
-          with Not_found ->
-            []
-        in
-        TerminalMap.add tok (prod :: prods) reductions
-      in
-
       (* Build the reduction table. Here, we gather all potential
          reductions, without attempting to solve shift/reduce
          conflicts on the fly, because that would potentially hide
@@ -529,7 +517,7 @@ let () =
 
       let reductions =
         List.fold_left (fun reductions (toks, prod) ->
-          TerminalSet.fold (addl prod) toks reductions
+          Lr0.add_reductions prod toks reductions
         ) TerminalMap.empty (Lr0.reductions node.state)
       in
 

src/slr.ml

@@ -64,23 +64,6 @@ let make_slr_state (s : Lr0.node) : Lr0.concretelr1state =
     Item.Map.add item follow_nt accu
   ) s Item.Map.empty
 
-(* Insertion of a new reduce action into the table of reductions. Copied
-   from [Lr1] (boo, hiss). *)
-
-let addl prod tok reductions =
-  let prods =
-    try
-      TerminalMap.lookup tok reductions
-    with Not_found ->
-      []
-  in
-  TerminalMap.add tok (prod :: prods) reductions
-
-(* Same thing, for a set of tokens. *)
-
-let addl prod toks reductions =
-  TerminalSet.fold (addl prod) toks reductions
-
 (* The following function turns a closed LR(1) state into a map of terminal
    symbols to reduction actions. Copied from a related function in [Lr0]. *)
 
@@ -88,7 +71,7 @@ let reductions (s : Lr0.concretelr1state) : Production.index list TerminalMap.t
   Item.Map.fold (fun item toks reductions ->
     match Item.classify item with
     | Item.Reduce prod ->
-        addl prod toks reductions
+        Lr0.add_reductions prod toks reductions
     | Item.Shift _ ->
         reductions
   ) s TerminalMap.empty