♻️ register globals in env before compilation

src/Mamarracho.hs

@@ -17,18 +17,27 @@ compile :: Program -> MamCode
 compile prog = showCode $ getCode $ execState (compile' prog) initState
 
 compile' :: Program -> Mam ()
-compile' []            = return ()
-compile' (def:program) = do
+compile' prog = registerGlobals prog >> compile'' prog
+
+registerGlobals :: Program -> Mam ()
+registerGlobals                  [] = return ()
+registerGlobals ((Def x _):program) = do
+  extendEnv (x, BRegister $ Global $ "G_" ++ x)
+  registerGlobals program
+
+compile'' :: Program -> Mam ()
+compile'' []            = return ()
+compile'' (def:program) = do
   compileDef def
   compile' program
 
 compileDef :: Definition -> Mam ()
-compileDef (Def _id e) = do
-  let greg = Global $ "G_" ++ _id
-  compileExpr e greg
-  extendEnv (_id, BRegister greg)
-  return ()
-
+compileDef (Def x e) = do
+  res <- lookupEnv x
+  case res of
+    Just (BRegister reg) -> compileExpr e reg
+    _ -> error $ "GLOBAL " ++ x ++ " SHOULD BE DEFINED"
+  
 compileExpr :: Expr -> Reg -> Mam ()
 compileExpr (ExprVar _id)            reg = compileVariable _id reg
 compileExpr (ExprNumber n)           reg = compilePrimitiveValue tagNumber n reg

src/State.hs

@@ -1,8 +1,7 @@
 module State where
 
 import Control.Monad.State (State, MonadState(get, put), gets)
-import Types (Instruction (Comment), StackEnv, ID, Binding(..), Env, Reg(Local), Label)
-import Data.List (intercalate)
+import Types (Instruction(..), StackEnv, ID, Binding(..), Env, Label)
 
 type Mam = State MamState
 
@@ -48,16 +47,6 @@ getEnv = gets (head . env)
 lookupEnv :: ID -> Mam (Maybe Binding)
 lookupEnv x = lookup x <$> getEnv
 
-lookupEnvRegister :: ID -> Mam Reg
-lookupEnvRegister x = do
-  env' <- getEnv
-  let regEnv = filter (isReg . snd) env'
-  case lookup x regEnv of
-    Just (BRegister reg) -> return reg
-    _ -> do
-      _ <- lookupEnvError x
-      return $ Local "_err"
-
 isReg :: Binding -> Bool
 isReg (BRegister _) = True
 isReg (BEnclosed _) = False
@@ -81,16 +70,6 @@ popEnv = do
   put $ mam { env = tail $ env mam }
   return $ head $ env mam
 
-lookupEnvError :: ID -> Mam String
-lookupEnvError x = do
-  env' <- getEnv
-  stackEnv' <- getStackEnv
-  let stackEnv'' = map show stackEnv'
-  error $ "'" ++ show x ++ "' is not defined in "
-    ++ show env'
-    ++ "\nStackEnv: \n"
-    ++ intercalate "\n" stackEnv''
-
 -- Code Stack
 
 getStack :: Mam Stack

src/Types.hs

@@ -12,7 +12,7 @@ type StackEnv = [Env]
 
 type NumOp = (Reg, Reg, Reg) -> Instruction
 
-data VarType = TPrinter | TOper | TVar
+data VarType = TPrinter | TOper | TVar deriving Show
 
 data Reg = Global String
          | Local  String