`sig
val read_name_tree :
Pdf.t -> Pdf.pdfobject -> (string * Pdf.pdfobject) list
val read_number_tree :
Pdf.t -> Pdf.pdfobject -> (string * Pdf.pdfobject) list
val build_name_tree :
bool -> Pdf.t -> (string * Pdf.pdfobject) list -> Pdf.pdfobject
val merge_name_trees_no_clash :
Pdf.t -> Pdf.pdfobject list -> Pdf.pdfobject
val merge_number_trees_no_clash :
Pdf.t -> Pdf.pdfobject list -> Pdf.pdfobject
end`