method menu_ctx (selection : string option) =
let l =
match selection with
None -> []
| Some dir ->
[
`I (M.add_dir, self#add_dir dir) ;
`I (M.update_dir, self#update_dir dir) ;
`I (M.commit_dir, self#commit_dir dir) ;
`I (M.tag_dir, self#tag_dir dir) ;
]
in
match l with
[] -> base#menu_ctx selection
| _ -> l @ (`S :: base#menu_ctx selection)