Городилов Е. В. гр. 2304

.gitignore

@@ -3,3 +3,7 @@
 /Driver.cmo
 /Expr.cmi
 /Expr.cmo
+_build
+_tags
+rc.byte
+rc.native

regression/Makefile

@@ -1,12 +1,7 @@
-TESTS=test001 test002 test012 test013 
+TESTS=test001 test002 test003 test004 test005 test006 test007 test008 test009 test010 test012 test013 test014 test015 test016 test017 test018 test019 test020 test021 test022 test023  
 
-# More expressions:
-# test003 test004 test005 test006 test007 test008 
-
-# Later:
-# test009 test010 test 11
-# test014 test015 test016 test017 test018 test019 test020 test021 test022 test023 test024 test025 test026 
-# test027 test028 test029 test030 
+# test019 test020 test021 test022 test023 test024 test025 test026 test017 test018 
+# test027 test028 test029 test030  test011 test014 test015 test016 
 
 .PHONY: check $(TESTS) 
 

src/Driver.ml

@@ -8,7 +8,7 @@ let parse filename =
   Util.parse 
     (object 
        inherit Matcher.t s 
-       inherit Util.Lexers.ident ["read"; "write"; "skip"] s
+       inherit Util.Lexers.ident ["read"; "write"; "skip"; "if"; "fi"; "then"; "else"; "while"; "do"; "od"; "repeat"; "until"; "for"] s
        inherit Util.Lexers.decimal s
        inherit Util.Lexers.skip [
          Matcher.Skip.whitespaces " \t\n";
@@ -48,4 +48,3 @@ let main =
     | `Fail er -> Printf.eprintf "Syntax error: %s\n" er
   with Invalid_argument _ ->
     Printf.printf "Usage: rc [-i] <input file.expr>\n"
-

src/Interpret.ml

@@ -1,49 +1,46 @@
 open Language
 
-(* Interpreter for expressions *)
 module Expr =
   struct
-
     open Expr
+    open Language.BinOp
 
     let rec eval expr st = 
       let eval' e = eval e st in
       match expr with
       | Var   x     -> st x
+
       | Const z     -> z
-      | Add  (x, y) -> eval' x + eval' y
-      | Mul  (x, y) -> eval' x * eval' y
-
+
+      | Binop  (op, x, y) -> (apply op) (eval' x) (eval' y)
   end
 
-(* Interpreter for statements *)
 module Stmt =
   struct
-
     open Stmt
 
-    (* State update primitive *) 
     let update st x v = fun y -> if y = x then v else st y 
 
     let rec eval stmt ((st, input, output) as conf) =
       match stmt with
       | Skip          -> conf
+
       | Assign (x, e) -> (update st x (Expr.eval e st), input, output)
-      | Read    x     -> 
-	  let z :: input' = input in
-	  (update st x z, input', output)
+
+      | Read    x     -> let z :: input' = input in (update st x z, input', output)
+      
       | Write   e     -> (st, input, output @ [Expr.eval e st])
+
       | Seq (s1, s2)  -> eval s1 conf |> eval s2 
-
+
+      | If (e, s1, s2) -> if (Expr.eval e st) <> 0 then (eval s1 conf) else (eval s2 conf)
+
+      | While (e, s)   -> if (Expr.eval e st) <> 0 then (eval stmt (eval s conf)) else conf
   end
 
 module Program =
   struct
-
     let eval p input = 
-      let (_, _, output) = 
-	Stmt.eval p ((fun _ -> failwith "undefined variable"), input, []) 
-      in
-      output
-
-  end
+      let (_, _, output) = Stmt.eval p ((fun _ -> failwith "undefined variable"), input, []) 
+      in output
+  end

src/Language.ml

@@ -1,54 +1,113 @@
-(* AST for expressions *)
+open Ostap 
+open Matcher
+
 module Expr =
   struct
-
     type t =
     | Var   of string
     | Const of int
-    | Add   of t * t
-    | Mul   of t * t 
+    | Binop of string * t * t
 
     ostap (
-      parse: x:mull "+" y:parse {Add (x,y)} | mull;
-      mull : x:prim "*" y:mull  {Mul (x,y)} | prim; 
-      prim : 
-        n:DECIMAL       {Const n}  
-      | e:IDENT         {Var e}
-      | -"(" parse -")" 
-    )
+      parse:
+        orins;
+
+      orins:
+        l:andins suf:(("!!") andins)* {
+           List.fold_left (fun l (op, r) -> Binop (Token.repr op, l, r)) l suf
+        }
+      | andins;
+
+      andins:
+        l:cmp suf:(("&&") cmp)* {
+           List.fold_left (fun l (op, r) -> Binop (Token.repr op, l, r)) l suf
+        }
+      | cmp;
 
+      cmp:
+        l:add suf:(("<=" | "<" | ">=" | ">" | "==" | "!=") add)* {
+           List.fold_left (fun l (op, r) -> Binop (Token.repr op, l, r)) l suf
+        }
+      | add;
+
+      add:
+        l:mull suf:(("+" | "-") mull)* {
+          List.fold_left (fun l (op, r) -> Binop (Token.repr op, l, r)) l suf
+        }
+      | mull;
+
+      mull:
+        l:prim suf:(("*" | "/" | "%") prim)* {
+           List.fold_left (fun l (op, r) -> Binop (Token.repr op, l, r)) l suf
+        }
+      | prim;
+
+      prim:
+        n:DECIMAL {Const n}
+      | x:IDENT   {Var   x}
+      | -"(" parse -")"
+    )
   end
 
-(* AST statements/commands *)
 module Stmt =
   struct
-
     type t =
     | Skip
     | Assign of string * Expr.t
     | Read   of string
     | Write  of Expr.t
     | Seq    of t * t
+    | If     of Expr.t * t * t
+    | While  of Expr.t * t
 
     let expr = Expr.parse
 
     ostap (
       simp: x:IDENT ":=" e:expr  {Assign (x, e)}
       | %"read"  "(" x:IDENT ")" {Read x}
       | %"write" "(" e:expr  ")" {Write e}
-      | %"skip"                  {Skip};
-
+      | %"skip"                  {Skip}
+      | %"if"        e:!(Expr.parse)
+        %"then"      s1:!(parse)
+        %"else"      s2:!(parse)
+        %"fi"                            {If (e, s1, s2)}
+      | %"if"        e:!(Expr.parse)
+        %"then"      s1:!(parse)
+        %"fi"                            {If (e, s1, Skip)}
+      | %"while"     e:!(Expr.parse)
+        %"do"        s:!(parse)
+        %"od"                            {While (e, s)}
+      | %"repeat"    s:!(parse)
+        %"until"     e:!(Expr.parse)     {Seq (s, While (Binop ("==", e, Const 0), s))}
+      | %"for"       i:!(parse) "," n:!(Expr.parse) "," b:!(parse)
+        %"do"        a:!(parse)
+        %"od"                            {Seq (i, (While (n, Seq (a, b))))};
       parse: s:simp ";" d:parse {Seq (s,d)} | simp 
     )
+  end
+
 
+module BinOp = 
+    struct
+      let apply op =
+        match op with
+        | "+"  -> fun x y -> x + y
+        | "*"  -> fun x y -> x * y
+        | "-"  -> fun x y -> x - y
+        | "/"  -> fun x y -> x / y
+        | "%"  -> fun x y -> x mod y
+        | "<"  -> fun x y -> if x < y then 1 else 0
+        | "<=" -> fun x y -> if x <= y then 1 else 0
+        | ">"  -> fun x y -> if x > y then 1 else 0
+        | ">=" -> fun x y -> if x >= y then 1 else 0
+        | "==" -> fun x y -> if x = y then 1 else 0
+        | "!=" -> fun x y -> if x <> y then 1 else 0
+        | "&&" -> fun x y -> if (x <> 0) && (y <> 0) then 1 else 0
+        | "!!" -> fun x y -> if (x <> 0) || (y <> 0) then 1 else 0
   end
 
 module Program =
   struct
-
     type t = Stmt.t
-
     let parse = Stmt.parse
-
   end
-