Something like [on¦off¦error] is enough, for that simple case. ;) ----- Reply message ----- Da: "Soumen" <soumen78@gmail.com> Data: mer, feb 17, 2010 11:58 Oggetto: [Boost-users] [program_options][1.35] validating string value A: <boost-users@lists.boost.org> Using regex can help you, maybe? Say, my switch name is "semantic_check" and possible values are "on" (turns on the checker, issues warning when something fails), "off" and "error" (changes severity of warning to error). Could you cite an example code snippet me how regex may help? Regards, ~ Soumen -- View this message in context: http://old.nabble.com/-program_options--1.35--validating-string-value-tp2762... Sent from the Boost - Users mailing list archive at Nabble.com. _______________________________________________ Boost-users mailing list Boost-users@lists.boost.org http://lists.boost.org/mailman/listinfo.cgi/boost-users