ast.icl

   1 implementation module ast
   2
   3 import StdEnv
   4 import Data.Either
   5 import Text
   6 import int
   7
   8 instance toString Function where
   9         toString (Function i a e) = concat [toString i, " ", join " " (map toString a), " = ", toString e]
  10
  11 instance toString Expression where
  12         toString (Lit v) = toString v
  13         toString (Var s) = toString s
  14         toString (App l r) = concat ["(", toString l, " ", toString r, ")"]
  15         toString (Lambda a e) = concat ["(\\", toString a, ". ", toString e, ")"]
  16         toString (Let ns r) = concat
  17                 [ "let ", concat [concat ["\t", toString n, " = ", toString v, "\n"]\\(n, v)<-ns]
  18                 , "in\n", toString r]
  19         toString _ = abort "toString Expression not implemented"
  20
  21 instance toString Value where
  22         toString (Int i) = toString i
  23         toString (Bool b) = toString b
  24         toString (Lambda` v a) = toString (Lambda v a)
  25         toString (Builtin a) = "builtin"
  26
  27 instance toString Type where
  28         toString (TVar a) = toString a
  29         toString TInt = "Int"
  30         toString TBool = "Bool"
  31         toString (TApp a b) = concat ["(", toString a, " ", toString b, ")"]
  32         toString (a --> b) = concat ["(", toString a, " -> ", toString b, ")"]
  33
  34 instance toString TypeDef where
  35         toString (TypeDef name args def) = join " " ["::",toString name:map toString args]
  36                 +++ " = " +++ join " | " [join " " [toString c:map toString d]\\(c, d)<-def]