fixed a cons bug and added tests

ps4/Makefile

@@ -4,7 +4,7 @@
 # change to a different ocamlc if you prefer (e.g., ocamlopt)
 COMPILER=ocamlc
 
-all: clean cish scish
+all: clean cish cish_stdin scish scish_stdin
 
 mips:
 	$(COMPILER) -c word32.ml
@@ -23,6 +23,10 @@ cish: mips
 	$(COMPILER) -c cish.ml
 	$(COMPILER) -o ps4_cish cish_ast.cmo cish_parse.cmo cish_lex.cmo cish_eval.cmo word32.cmo mips.cmo utility.cmo cish_compile.cmo cish.cmo
 
+cish_stdin: cish
+		$(COMPILER) -c cish_stdin.ml
+		$(COMPILER) -o ps4_cish_stdin cish_ast.cmo cish_parse.cmo cish_lex.cmo cish_eval.cmo word32.cmo mips.cmo utility.cmo cish_compile.cmo cish_stdin.cmo
+
 scish: cish mips	
 	$(COMPILER) -c cish_ast.ml
 	$(COMPILER) -c scish_ast.ml
@@ -37,6 +41,11 @@ scish: cish mips
 	$(COMPILER) -c scish.ml
 	$(COMPILER) -o ps4_scish cish_ast.cmo cish_parse.cmo cish_lex.cmo scish_ast.cmo scish_parse.cmo scish_lex.cmo scish_eval.cmo utility.cmo word32.cmo mips.cmo environment.cmo scish_compile.cmo scish.cmo
 
+scish_stdin: scish
+	$(COMPILER) -c scish_stdin.ml
+	$(COMPILER) -o ps4_scish_stdin cish_ast.cmo cish_parse.cmo cish_lex.cmo scish_ast.cmo scish_parse.cmo scish_lex.cmo scish_eval.cmo utility.cmo word32.cmo mips.cmo environment.cmo scish_compile.cmo scish_stdin.cmo
+
+
 clean:
-	rm -rf *.cmo *.cmi ps4_cish ps4_scish cish_parse.ml cish_parse.mli cish_lex.ml scish_parse.ml scish_parse.mli scish_lex.ml
+	rm -rf *.cmo *.cmi ps4_cish ps4_scish ps4_cish_stdin ps4_scish_stdin cish_parse.ml cish_parse.mli cish_lex.ml scish_parse.ml scish_parse.mli scish_lex.ml
 

ps4/cish_stdin.ml

@@ -0,0 +1,27 @@
+open Cish_ast
+open Cish_eval
+
+(* This magic is used to glue the generated lexer and parser together.
+ * Expect one command-line argument, a file to parse.
+ * You do not need to understand this interaction with the system. *)
+let parse_file() =
+  let argv = Sys.argv in
+  let _ = 
+    if Array.length argv != 2
+    then (prerr_string ("usage: " ^ argv.(0) ^ " [file-to-parse]\n");
+    exit 1) in
+  let ch = open_in argv.(1) in
+  Cish_parse.program Cish_lex.lexer (Lexing.from_channel ch)
+
+let parse_stdin() = 
+  Cish_parse.program Cish_lex.lexer (Lexing.from_channel stdin)
+
+let compile_prog prog =
+  Cish_compile.result2string (Cish_compile.compile prog )
+
+(* Reads in cish code and evaluates it *)
+let _ =
+  let prog = parse_stdin() in
+  let ans = eval prog in
+  print_string ("answer = "^(val2string ans)^"\n")
+  (* print_string (compile_prog prog) *)

ps4/scish_compile.ml

@@ -72,9 +72,10 @@ let rec compile_exp_r ( t_expr : Scish_ast.exp )
                                  let store_stmt1 = cish_stmt_from_str ("*(" ^ tuple_address ^ ") = " ^ result_name ^ ";") in
                                  (* Compile second expression, placing result in result *)
                                  let (f_list2, scope2, stmt2) = compile_exp_r (List.nth exps 1) f_list1 scope1 in
-                                 (* Store result in second word at tupele's address *)
+                                 (* Store result in second word at tuple's address *)
                                  let store_stmt2 = cish_stmt_from_str ("*(" ^ tuple_address ^ "+4) = " ^ result_name ^ ";") in
-                                     (f_list2, scope2, (init_var tuple_address (seqs [init_stmt; stmt1; store_stmt1; stmt2; store_stmt2])))
+                                 let mv_result   = cish_stmt_from_str (result_name^" = "^tuple_address^";") in
+                                     (f_list2, scope2, (init_var tuple_address (seqs [init_stmt; stmt1; store_stmt1; stmt2; store_stmt2; mv_result])))
                                          (* create a pair *)
                            | Fst -> access_mem (List.hd exps) f_list scope 0 
                            | Snd -> access_mem (List.hd exps) f_list scope 4

ps4/scish_stdin.ml

@@ -0,0 +1,31 @@
+open Scish_ast
+open Scish_eval
+
+(* This magic is used to glue the generated lexer and parser together.
+ * Expect one command-line argument, a file to parse.
+ * You do not need to understand this interaction with the system. *)
+let parse_file () =
+  let argv = Sys.argv in
+  let _ = 
+    if Array.length argv != 2
+    then (prerr_string ("usage: " ^ argv.(0) ^ " [file-to-parse]\n");
+    exit 1) in
+  let ch = open_in argv.(1) in
+  Scish_parse.program Scish_lex.lexer (Lexing.from_channel ch)
+
+let parse_stdin () = 
+  Scish_parse.program Scish_lex.lexer (Lexing.from_channel stdin)
+
+let compile_prog prog = Scish_compile.compile_exp prog
+
+let run_prog prog = Scish_eval.run prog
+
+let dump p = print_string (Cish_ast.prog2string p)
+
+let _ =
+  let prog = parse_stdin() in
+(*
+let _ =  print_string ("answer = "^(string_of_int ans)^"\n") in
+*)
+
+  dump (compile_prog prog)

ps4/test/if.scish

@@ -0,0 +1 @@
+((lambda (x) (if (< x 5) (* x 5) (* x 2))) 10)

ps4/test/sample_add.scish

@@ -0,0 +1 @@
+(+ 5 4)

ps4/test/sample_cons.scish

@@ -0,0 +1 @@
+(fst (cons 5 4))

ps4/test/shadow.scish

@@ -0,0 +1 @@
+(((lambda (x) (lambda (x) (+ x x))) 42) 3)

ps4/test/square.scish

@@ -0,0 +1 @@
+((lambda (x) (* x x)) 5)