Abandon $ for index field parameter, cmdliner complains

cli/index.ml

@@ -41,13 +41,13 @@ type t = { dir : string; index_path: string; pck : Header_pack.t }
 
 let index r print title auth locs peers =
 	let edit name index param = if print then index else match param with
-	| Some "$" -> text_editor name index | Some p -> p
+	| Some "" -> text_editor name index | Some p -> p
 	| None -> index in
 	let edits name index param = if print then index else match param with
-	| Some "$" -> text_editor_lines name index | Some p -> String_set.list_of_csv p
+	| Some "" -> text_editor_lines name index | Some p -> String_set.list_of_csv p
 	| None -> index in
 	let edits_mp name index param = if print then index else match param with
-	| Some "$" -> Header_pack.str_list (text_editor_lines name (Header_pack.to_str_list index))
+	| Some "" -> Header_pack.str_list (text_editor_lines name (Header_pack.to_str_list index))
 	| Some p -> Header_pack.str_list (String_set.list_of_csv p)
 	| None -> index in
 	let info = Header_pack.{ r.pck.info with
@@ -78,13 +78,13 @@ let load dir =
 open Cmdliner
 let term =
 	let print= Arg.(value & flag & info ["print"] ~doc:"print info") in
-	let title= Arg.(value & opt ~vopt:(Some "$") (some string) None & info ["t"; "title"]
+	let title= Arg.(value & opt ~vopt:(Some "") (some string) None & info ["t"; "title"]
 		~docv:"string" ~doc:"Title for index") in
-	let auth = Arg.(value & opt ~vopt:(Some "$") (some string) None & info ["a"; "authors"]
+	let auth = Arg.(value & opt ~vopt:(Some "") (some string) None & info ["a"; "authors"]
 		~docv:"comma-separated names" ~doc:"Index authors") in
-	let locs = Arg.(value & opt ~vopt:(Some "$") (some string) None & info ["l"; "locations"]
+	let locs = Arg.(value & opt ~vopt:(Some "") (some string) None & info ["l"; "locations"]
 		~docv:"comma-separated URLs" ~doc:"repository URLs") in
-	let peers= Arg.(value & opt ~vopt:(Some "$") (some string) None & info ["p"; "peers"]
+	let peers= Arg.(value & opt ~vopt:(Some "") (some string) None & info ["p"; "peers"]
 		~docv:"comma-separated URLs" ~doc:"URLs to other known text repositories") in
 	let dir  = Arg.(value & pos 0 string "." & info []
 		~docv:"directory to index") in