module Id where

-- identifiers, fixed for all logics

data ID = Simple_Id String

| Compound_Id (String,[ID])

type Pos = (Int, Int) -- line, column

nullPos = (0,0) -- dummy position

-- tokens as supplied by the scanner

data Token = Token(String, Pos) deriving Show

instance Eq Token where

Token(s1, _) == Token(s2, _) = s1 == s2

instance Ord Token where

Token(s1, _) <= Token(s2, _) = s1 <= s2

instance Show Token where

showsPrec _ Token(t, _) = showString t

-- spezial tokens

type Keyword = Token

type TokenOrPlace = Token

-- move to scanner

setPos(Token(t, _), p) = Token(t, p)

place = "__"

isPlace(Token(t, _)) = t == place

-- an identifier may be mixfix (though not for a sort) and compound

data Id = Id([TokenOrPlace], [Id]) deriving (Eq, Ord)

instance Show Id where

showsPrec d Id(ts, is) = showString (foldl ++ "" ts) ++ (show is)