X-Git-Url: http://git.lukelau.me/?a=blobdiff_plain;f=AST.hs;h=1e505af4f47116e401e2523f10c90ac1c466c360;hb=8d014ae9c14ab12436acad496ba2726e39b4d69a;hp=e491b648a7d45f7bd3b419b0e3ff6a8c215cbd83;hpb=b73dcb0743e0d42c93e21aa12691ee324b7d56f0;p=kaleidoscope-hs.git

diff --git a/AST.hs b/AST.hs
index e491b64..1e505af 100644
--- a/AST.hs
+++ b/AST.hs
@@ -4,9 +4,11 @@ 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]
+          | If Expr Expr Expr
   deriving Show
 
 data BinOp = Add | Sub | Mul | Cmp Ordering
@@ -15,7 +17,11 @@ data BinOp = Add | Sub | Mul | Cmp Ordering
 instance Read Expr where
   readPrec = parens $ choice [ parseNum
                              , parseVar
+                             , parseCall
+                             , parseIf
                              , parseBinOp "<" 10 (Cmp LT)
+                             , parseBinOp ">" 10 (Cmp GT)
+                             , parseBinOp "==" 10 (Cmp EQ)
                              , parseBinOp "+" 20 Add
                              , parseBinOp "-" 20 Sub
                              , parseBinOp "*" 40 Mul
@@ -30,6 +36,20 @@ 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)
+          parseIf = do
+            lift $ skipSpaces >> string "if" >> skipSpaces
+            cond <- readPrec
+            lift $ skipSpaces >> string "then" >> skipSpaces
+            thenE <- readPrec
+            lift $ skipSpaces >> string "else" >> skipSpaces
+            elseE <- readPrec
+            return (If cond thenE elseE)
             
 data Prototype = Prototype String [String]
   deriving Show