Cleanup in calc-inspection. Isolated two more files.

demos/calc-inspection/CalcErrorReporting.ml

+open Parser
+open Parser.MenhirInterpreter
+
+(* In order to submit artificial tokens to the parser, we need a function that
+   converts a terminal symbol to a (dummy) token. Unfortunately, we cannot (in
+   general) auto-generate this code, because it requires making up semantic
+   values of arbitrary OCaml types. *)
+
+let terminal2token (type a) (symbol : a terminal) : token =
+  match symbol with
+  | T_TIMES ->
+      TIMES
+  | T_RPAREN ->
+      RPAREN
+  | T_PLUS ->
+      PLUS
+  | T_MINUS ->
+      MINUS
+  | T_LPAREN ->
+      LPAREN
+  | T_INT ->
+      INT 0
+  | T_EOL ->
+      EOL
+  | T_DIV ->
+      DIV
+  | T_error ->
+      assert false
+

demos/calc-inspection/CalcErrorReporting.mli

+open Parser.MenhirInterpreter
+
+(* This module offers the functionality required by the functor
+   [ErrorReporting.Printers.Make]. *)
+
+val terminal2token: _ terminal -> token
+

demos/calc-inspection/CalcPrinters.ml

+open Parser.MenhirInterpreter
+
+(* In order to print syntax error messages and/or debugging information, we
+   need a symbol printer. *)
+
+let print_symbol symbol : string =
+  match symbol with
+  | X (T T_TIMES) ->
+      "*"
+  | X (T T_RPAREN) ->
+      ")"
+  | X (T T_PLUS) ->
+      "+"
+  | X (T T_MINUS) ->
+      "-"
+  | X (T T_LPAREN) ->
+      "("
+  | X (T T_INT) ->
+      "INT"
+  | X (N N_expr) ->
+      "expr"
+  | X (N N_main) ->
+      "main"
+  | X (T T_EOL) ->
+      "EOL"
+  | X (T T_DIV) ->
+      "/"
+  | X (T T_error) ->
+      "error"
+
+(* In order to print a view of the stack that includes semantic values,
+   we need an element printer. (If we don't need this feature, then
+   [print_symbol] above suffices.) *)
+
+let print_element e : string =
+  match e with
+  | Element (s, v, _, _) ->
+      match incoming_symbol s with
+      | T T_TIMES ->
+          "*"
+      | T T_RPAREN ->
+          ")"
+      | T T_PLUS ->
+          "+"
+      | T T_MINUS ->
+          "-"
+      | T T_LPAREN ->
+          "("
+      | T T_INT ->
+          string_of_int v
+      | N N_expr ->
+          string_of_int v
+      | N N_main ->
+          string_of_int v
+      | T T_EOL ->
+          ""
+      | T T_DIV ->
+          "/"
+      | T T_error ->
+          "error"
+
+(* The public functions. *)
+
+let print = prerr_string
+let print_symbol s = print (print_symbol s)
+let print_element = Some (fun s -> print (print_element s))
+

demos/calc-inspection/CalcPrinters.mli

+open Parser.MenhirInterpreter
+
+(* This module offers the functionality required by the functor
+   [MenhirLib.Printers.Make]. *)
+
+val print: string -> unit
+val print_symbol: xsymbol -> unit
+val print_element: (element -> unit) option
+

demos/calc-inspection/calc.ml

 open MenhirLib.General
 open Parser.MenhirInterpreter
 
-(* --------------------------------------------------------------------------- *)
-
-(* In order to submit artificial tokens to the parser, we need a function that
-   converts a terminal symbol to a (dummy) token. Unfortunately, we cannot (in
-   general) auto-generate this code, because it requires making up semantic
-   values of arbitrary OCaml types. *)
-
-let terminal2token (type a) (symbol : a terminal) : token =
-  let open Parser in
-  match symbol with
-  | T_TIMES ->
-      TIMES
-  | T_RPAREN ->
-      RPAREN
-  | T_PLUS ->
-      PLUS
-  | T_MINUS ->
-      MINUS
-  | T_LPAREN ->
-      LPAREN
-  | T_INT ->
-      INT 0
-  | T_EOL ->
-      EOL
-  | T_DIV ->
-      DIV
-  | T_error ->
-      assert false
-
-(* In order to print syntax error messages and/or debugging information, we
-   need a symbol printer. *)
-
-let print_symbol symbol =
-  match symbol with
-  | X (T T_TIMES) ->
-      "*"
-  | X (T T_RPAREN) ->
-      ")"
-  | X (T T_PLUS) ->
-      "+"
-  | X (T T_MINUS) ->
-      "-"
-  | X (T T_LPAREN) ->
-      "("
-  | X (T T_INT) ->
-      "INT"
-  | X (N N_expr) ->
-      "expr"
-  | X (N N_main) ->
-      "main"
-  | X (T T_EOL) ->
-      "EOL"
-  | X (T T_DIV) ->
-      "/"
-  | X (T T_error) ->
-      "error"
-
-(* In order to print a view of the stack that includes semantic values,
-   we need an element printer. (If we don't need this feature, then
-   [print_symbol] above suffices.) *)
-
-let print_element e : string =
-  match e with
-  | Element (s, v, _, _) ->
-      match incoming_symbol s with
-      | T T_TIMES ->
-          "*"
-      | T T_RPAREN ->
-          ")"
-      | T T_PLUS ->
-          "+"
-      | T T_MINUS ->
-          "-"
-      | T T_LPAREN ->
-          "("
-      | T T_INT ->
-          string_of_int v
-      | N N_expr ->
-          string_of_int v
-      | N N_main ->
-          string_of_int v
-      | T T_EOL ->
-          ""
-      | T T_DIV ->
-          "/"
-      | T T_error ->
-          "error"
-
-(* --------------------------------------------------------------------------- *)
-
-(* TEMPORARY comment *)
+(* Instantiate [MenhirLib.Printers] for our parser. This requires providing a
+   few printing functions -- see [CalcPrinters]. *)
 
 module P =
-  MenhirLib.Printers.Make (Parser.MenhirInterpreter) (struct
-    let print s = Printf.fprintf stderr "%s" s
-    let print_symbol s = print (print_symbol s)
-    let print_element = Some (fun s -> print (print_element s))
-  end)
+  MenhirLib.Printers.Make
+    (Parser.MenhirInterpreter)
+    (CalcPrinters)
+
+(* Instantiate [MenhirLib.ErrorReporting] for our parser. This requires
+   providing a few functions -- see [CalcErrorReporting]. *)
 
 module E =
-  MenhirLib.ErrorReporting.Make(Parser.MenhirInterpreter) (struct
-    let terminal2token = terminal2token
-  end)
+  MenhirLib.ErrorReporting.Make
+    (Parser.MenhirInterpreter)
+    (CalcErrorReporting)
 
 let print_explanation explanation =
   (* TEMPORARY not satisfactory at all *)