Added driver and parsing holes

src/Driver.ml

@@ -0,0 +1,41 @@
+open Ostap
+
+let parse infile =
+  let s = Util.read infile in
+  Util.parse
+    (object
+       inherit Matcher.t s
+       inherit Util.Lexers.decimal s
+       inherit Util.Lexers.skip [
+	 Matcher.Skip.whitespaces " \t\n";
+	 Matcher.Skip.lineComment "--";
+	 Matcher.Skip.nestedComment "(*" "*)"
+       ] s
+     end
+    )
+    (ostap (!(Language.parse) -EOF))
+
+let main =
+  try
+    let interpret  = Sys.argv.(1) = "-i"  in
+    let stack      = Sys.argv.(1) = "-s"  in
+    let infile     = Sys.argv.(2) in
+    match parse infile with
+    | `Ok ((_, stmt) as prog) ->
+       let rec read acc =
+         try
+	   let r = read_int () in
+	   Printf.printf "> ";
+	   read (acc @ [r]) 
+         with End_of_file -> acc
+       in
+       let input = read [] in	
+       let output = 
+	 if interpret 
+	 then Language.eval prog input 
+	 else SM.eval (SM.compile prog) input
+       in
+       List.iter (fun i -> Printf.printf "%d\n" i) output
+    | `Fail er -> Printf.eprintf "Syntax error: %s\n" er
+  with Invalid_argument _ ->
+    Printf.printf "Usage: rc [-i] <input file.expr>\n"

src/Language.ml

@@ -3,6 +3,9 @@
 *)
 open GT
 
+(* Opening a library for combinator-based syntax analysis *)
+open Ostap.Combinators
+       
 (* Simple expressions: syntax and semantics *)
 module Expr =
   struct
@@ -43,6 +46,11 @@ module Expr =
     *)
     let eval _ = failwith "Not implemented yet"
 
+    (* Statement parser *)
+    ostap (
+      parse: empty {failwith "Not implemented yet"}
+    )
+
   end
                     
 (* Simple statements: syntax and sematics *)
@@ -67,4 +75,26 @@ module Stmt =
     *)
     let eval _ = failwith "Not implemented yet"
 
+    (* Statement parser *)
+    ostap (
+      parse: empty {failwith "Not implemented yet"}
+    )
+      
   end
+
+(* The top-level definitions *)
+
+(* The top-level syntax category is statement *)
+type t = Stmt.t    
+
+(* Top-level evaluator
+
+     eval : t -> int list -> int list
+
+   Takes a program and its input stream, and returns the output stream
+*)
+let eval p i =
+  let _, _, o = Stmt.eval (Expr.empty, i, []) p in o
+
+(* Top-level parser *)
+let parse = Stmt.parse                                                     

src/Makefile

@@ -2,7 +2,7 @@ TOPFILE = rc
 OCAMLC = ocamlc
 OCAMLOPT = ocamlopt
 OCAMLDEP = ocamldep
-SOURCES = Syntax.ml Embedding.ml SM.ml
+SOURCES = Language.ml Embedding.ml SM.ml Driver.ml
 LIBS = GT.cma unix.cma re.cma re_emacs.cma re_str.cma
 CAMLP5 = -pp "camlp5o -I `ocamlfind -query GT.syntax` -I `ocamlfind -query ostap.syntax` pa_ostap.cmo pa_gt.cmo -L `ocamlfind -query GT.syntax`"
 PXFLAGS = $(CAMLP5)

src/SM.ml

@@ -14,7 +14,7 @@ type prg = insn list
 (* The type for the stack machine configuration: a stack and a configuration from statement
    interpreter
  *)
-type config = int list * Syntax.Stmt.config
+type config = int list * Language.Stmt.config
 
 (* Stack machine interpreter
 
@@ -26,7 +26,7 @@ let eval _ = failwith "Not yet implemented"
 
 (* Stack machine compiler
 
-     val compile : Syntax.Stmt.t -> prg
+     val compile : Language.Stmt.t -> prg
 
    Takes a program in the source language and returns an equivalent program for the
    stack machine