val verbose_lexing : bool refval verbose_parsing : bool refval exn_when_lexical_error : bool refval debug_lexer : bool refval show_parsing_error : bool refval error_recovery : bool refval sgrep_mode : bool refval cmdline_flags_verbose : unit -> (string * Arg.spec * string) listval cmdline_flags_debugging : unit -> (string * Arg.spec * string) listval sgrep_guard : 'a -> 'a