WIP lambdas

3 files changed, 37 insertions, 19 deletions

diff --git a/ast/CC/Source.hs b/ast/CC/Source.hs
index 81e691b..080b850 100644
--- a/ast/CC/Source.hs
+++ b/ast/CC/Source.hs
@@ -20,9 +20,11 @@ data Type = TFun Type Type
           | TInt
   deriving (Show, Read)
 
-data Expr = Call SourceRange Expr Expr
+data Expr = Lam SourceRange [(Name, SourceRange)] Expr
+          | Call SourceRange Expr Expr
           | Int SourceRange Int
           | Var SourceRange Name
+          | Annot SourceRange Expr Type
   deriving (Show, Read)
 
 instance Pretty Type where
@@ -31,6 +33,8 @@ instance Pretty Type where
         precParens p 2 (prettyPrec 3 a ++ " -> " ++ prettyPrec 2 b)
 
 instance HasRange Expr where
+    range (Lam sr _ _) = sr
     range (Call sr _ _) = sr
     range (Int sr _) = sr
     range (Var sr _) = sr
+    range (Annot sr _ _) = sr
diff --git a/ast/CC/Typed.hs b/ast/CC/Typed.hs
index 5b8ed38..535fd31 100644
--- a/ast/CC/Typed.hs
+++ b/ast/CC/Typed.hs
@@ -7,13 +7,10 @@ import CC.Pretty
 import CC.Types
 
 
-data ProgramT = ProgramT [DeclT]
+data ProgramT = ProgramT [DefT]
   deriving (Show, Read)
 
-data DeclT = DefT DefT  -- import?
-  deriving (Show, Read)
-
-data DefT = FunctionT TypeT Name [Name] ExprT
+data DefT = DefT Name ExprT
   deriving (Show, Read)
 
 data TypeT = TFunT TypeT TypeT
@@ -21,16 +18,17 @@ data TypeT = TFunT TypeT TypeT
            | TyVar Int
   deriving (Show, Read)
 
-data ExprT = CallT TypeT ExprT ExprT
+data ExprT = LamT TypeT Occ ExprT
+           | CallT TypeT ExprT ExprT
            | IntT Int
            | VarT Occ
   deriving (Show, Read)
 
--- | Occurrence of a variable
 data Occ = Occ Name TypeT
   deriving (Show, Read)
 
 exprType :: ExprT -> TypeT
+exprType (LamT typ _ _) = typ
 exprType (CallT typ _ _) = typ
 exprType (IntT _) = TIntT
 exprType (VarT (Occ _ typ)) = typ
@@ -55,10 +53,7 @@ instance Pretty ExprT where
             show n ++ " :: " ++ pretty t
 
 instance Pretty DefT where
-    pretty (FunctionT n e) = n ++ " = " ++ pretty e
-
-instance Pretty DeclT where
-    pretty (DefT def) = pretty def
+    pretty (DefT n e) = n ++ " = " ++ pretty e
 
 instance Pretty ProgramT where
-    pretty (ProgramT decls) = concatMap ((++ "\n") . pretty) decls
+    pretty (ProgramT defs) = concatMap ((++ "\n") . pretty) defs
diff --git a/parser/CC/Parser.hs b/parser/CC/Parser.hs
index d6c2239..d9e5b40 100644
--- a/parser/CC/Parser.hs
+++ b/parser/CC/Parser.hs
@@ -54,9 +54,31 @@ pTypeAtom :: Parser Type
 pTypeAtom = (wordToken "Int" >> return TInt) <|> between (token "(") (token ")") pType
 
 pExpr :: Parser Expr
-pExpr = lab "expression" $ do
-    atoms <- many1 pExprAtom
-    return (foldl1 (\a b -> Call (mergeRange (range a) (range b)) a b) atoms)
+pExpr = label (pCall <|> pLam) "expression"
+  where
+    pCall = do
+        atoms <- many1 pExprAtom
+        annot <- optionMaybe (do symbol "::"
+                                 p1 <- getPosition
+                                 ty <- pType
+                                 p2 <- getPosition
+                                 return (ty, SourceRange p1 p2))
+        let call = foldl1 (\a b -> Call (mergeRange (range a) (range b)) a b) atoms
+        case annot of
+            Just (ty, sr) -> return (Annot (mergeRange (range call) sr) call ty)
+            Nothing -> return call
+
+    pLam = do
+        p1 <- try $ do
+            whitespace
+            p <- getPosition
+            void (char '\\')
+            return p
+        names <- many1 pName
+        symbol "->"
+        body <- pExpr
+        p2 <- getPosition
+        return (Lam (SourceRange p1 p2) names body)
 
 pExprAtom :: Parser Expr
 pExprAtom =
@@ -106,9 +128,6 @@ emptyLines = (try (whitespace >> newline) >> emptyLines) <|> try (whitespace >>
 whitespace :: Parser ()
 whitespace = void (many (char ' '))
 
-lab :: String -> Parser a -> Parser a
-lab = flip label
-
 getPosition :: Parser SourcePos
 getPosition = do
     pos <- Text.Parsec.getPosition