Begin codegen
[kaleidoscope-hs.git] / AST.hs
diff --git a/AST.hs b/AST.hs
index 7dad3a19e91eab9f12657101bd224b5c81742d07..dfa43b7c60c0d0ced86a73268167b1b9584b9d74 100644 (file)
--- a/AST.hs
+++ b/AST.hs
@@ -4,17 +4,19 @@ import Data.Char
 import Text.Read 
 import Text.ParserCombinators.ReadP hiding ((+++), choice)
 
-data Expr = Num Float
+data Expr = Num Double
           | Var String
           | BinOp BinOp Expr Expr
+          | Call String [Expr]
   deriving Show
 
 data BinOp = Add | Sub | Mul | Cmp Ordering
   deriving Show
 
 instance Read Expr where
-  readPrec = choice [ parseNum
+  readPrec = parens $ choice [ parseNum
                              , parseVar
+                             , parseCall
                              , parseBinOp "<" 10 (Cmp LT)
                              , parseBinOp "+" 20 Add
                              , parseBinOp "-" 20 Sub
@@ -30,6 +32,12 @@ instance Read Expr where
               skipSpaces
             b <- readPrec
             return (BinOp op a b)
+          parseCall = do
+            func <- lift (munch1 isAlpha)
+            params <- lift $ between (char '(') (char ')') $
+                        sepBy (readS_to_P reads)
+                              (skipSpaces >> char ',' >> skipSpaces)
+            return (Call func params)
             
 data Prototype = Prototype String [String]
   deriving Show