+ where parseParens = step $ lift $
+ between (char '(') (char ')') (readS_to_P reads)
+ parseNum = Num <$> readPrec
+ parseVar = Var <$> lift (munch1 isAlpha)
+ parseCall = do
+ func <- lift (munch1 isAlpha)
+ params <- lift $ between (char '(') (char ')') $
+ sepBy (readS_to_P reads)
+ (skipSpaces >> char ',' >> skipSpaces)
+ return (Call func params)
+ parseBinOp s typ = step $ do
+ a <- prec 11 readPrec -- set recursion limit of 11
+ lift $ do
+ skipSpaces
+ string s
+ skipSpaces
+ BinOp typ a <$> readPrec
+ parseIf = do
+ lift $ do
+ string "if"
+ skipSpaces
+ cond <- step readPrec
+ lift $ do
+ skipSpaces
+ string "then"
+ skipSpaces
+ thenE <- step readPrec