1 files changed, 25 insertions, 7 deletions
diff --git a/src/Language/SimpleShell/Parser/Function.hs b/src/Language/SimpleShell/Parser/Function.hs
index a0c5a9b..f7a63f8 100644
--- a/src/Language/SimpleShell/Parser/Function.hs
+++ b/src/Language/SimpleShell/Parser/Function.hs
@@ -2,16 +2,17 @@
 
 module Language.SimpleShell.Parser.Function
   ( functionP
+  , functionP0
   )
 where
 
 
 import Language.SimpleShell.AST.Expr (Expr)
 import Language.SimpleShell.AST.Function (Function(..))
-import Language.SimpleShell.AST.Name (VarName)
-import Language.SimpleShell.AST.SimpleType (FunSig, Typed)
+import Language.SimpleShell.AST.Name (FunName, VarName)
+import Language.SimpleShell.AST.SimpleType (SimpleType, FunSig, Typed)
 import Language.SimpleShell.Parser (Parser, symbol, declareVars)
-import Language.SimpleShell.Parser.Expr (strongTermP)
+import Language.SimpleShell.Parser.Expr (strongTermP, strongTermP_)
 import Language.SimpleShell.Parser.Name (nameP, keyword)
 import Language.SimpleShell.Parser.SimpleType (simpleTypeP, forceType)
 
@@ -19,19 +20,36 @@ import Control.Applicative ((<|>))
 import Text.Megaparsec (sepBy)
 
 
-functionP :: Parser (FunSig, Function)
-functionP = do
+functionPrefixP :: Parser (SimpleType, FunName, [Typed VarName])
+functionPrefixP = do
   keyword "function"
   t' <- simpleTypeP
   fname <- nameP
   params <- symbol "(" *> paramP `sepBy` symbol "," <* symbol ")"
   symbol "="
-  let (ts, vars) = unzip params
+  return (t', fname, params)
+
+functionP :: Parser Function
+functionP = do
+  (t', fname, params) <- functionPrefixP
+  let vars = map snd params
   body <- forceType t' (bodyP params) <|> fail "Function return type mismatch."
-  return ((t', ts), Function fname vars body)
+  return $ Function fname vars body
+
+-- | First-pass function parser.
+functionP0 :: Parser (FunName, FunSig)
+functionP0 = do
+  (t', fname, params) <- functionPrefixP
+  let ts = map fst params
+  bodyP_
+  return (fname, (t', ts))
+
 
 paramP :: Parser (Typed VarName)
 paramP = (,) <$> simpleTypeP <*> nameP
 
 bodyP :: [Typed VarName] -> Parser (Typed Expr)
 bodyP params = declareVars params strongTermP
+
+bodyP_ :: Parser ()
+bodyP_ = strongTermP_