(* Generate a fresh variable from a given prefix, e.g. "counter" -> "counter$1"  *)
val fresh_var : string -> string

(* Default transformation traversal for AST nodes *)
val transform_children : (Ast.node -> Ast.node) -> Ast.node -> Ast.node

(*val visit_children : (Ast.node -> unit) -> Ast.node -> unit*)

(* Extract location from node *)
val locof : Ast.node -> Ast.loc