sig
val get_eqn :
Literals.t ->
Libzipperposition.Position.t ->
(Literals.term * Literals.term * bool) option
val get_arith :
Literals.t -> Libzipperposition.Position.t -> ArithLit.Focus.t option
val get_eqn_exn :
Literals.t ->
Libzipperposition.Position.t -> Literals.term * Literals.term * bool
val get_arith_exn :
Literals.t -> Libzipperposition.Position.t -> ArithLit.Focus.t
end