Nmm_ocaml : Common_utils.label_of_path

let label_of_path_opt (doc_settings : t_doc_settings) (path : t_path) : string option =
        match path with
        | [] -> None
        | hd :: tl ->
                match hd with
                | CH_NODE _ -> (
                        match doc_settings.ch_prefix, string_of_path doc_settings path with
                        | None, p -> Some p 
                        | Some (lbl,_), p -> Some (lbl ^ "\u{00A0}" ^ p)
                )
                | SEC_NODE _ -> (
                        match doc_settings.sec_prefix, string_of_path doc_settings path with
                        | None, p -> Some p 
                        | Some (lbl,_), p -> Some (lbl ^ "\u{00A0}" ^ p)
                )
                | APP_NODE _ -> (
                        match doc_settings.app_prefix, string_of_path doc_settings path with
                        | None, p -> Some p 
                        | Some (lbl,_), p -> Some (lbl ^ "\u{00A0}" ^ p)
                )
                | PAR_NODE _ -> (
                        match doc_settings.par_prefix, string_of_path doc_settings path with
                        | None, p -> Some p 
                        | Some (lbl,_), p -> Some (lbl ^ "\u{00A0}" ^ p)
                )
                | ITM_NODE _
                | BLT_NODE
                | DSP_LINE_NODE _ -> string_of_node_opt doc_settings tl hd
                | ABSTRACT_NODE -> (
                        match doc_settings.abstract_hdr with
                        |Some (lbl,_) -> Some lbl
                        |None -> None
                )
                | REFS_NODE -> (
                        match doc_settings.refs_hdr with
                        |Some (lbl,_) -> Some lbl
                        |None -> None
                )
                |NTE_NODE n -> Some (superscript_string_of_int n)
                | _ -> None