--
-- Abstract syntax for expressions
-- Refers to a Nonterminal for Bindings
--
-- Note that we only share the definition of this syntax, not the instantation
-- to a Haskell data type. This has to be done for each choice of the
-- Bindings-nonterminal.
--

DATA Expr
  | String
      pos : {Pos}
      str : {String}
  | Int
      pos : {Pos}
      n   : {Int}
  | Ident
      nm : {Identifier}
  | Alt
      pos      : {Pos}
      nm       : {Identifier}
      bindings : Bindings
  | Parens
      expr : Expr