sig
type file = BottomUpAst.clause list
and clause = Clause of BottomUpAst.literal * BottomUpAst.literal list
and literal = Atom of string * BottomUpAst.term list
and term = Var of string | Const of string | Quoted of string
and query =
Query of BottomUpAst.term list * BottomUpAst.literal list *
BottomUpAst.literal list
end