Hello Boosters, maybe I am blind as a bat, but I was looking for a possibility to check a given regular expression for its general validity.
To get rid of my problem to define "validity" I delegate its definition to "everything which would lead to the throw of boost::bad_expression" of all reg_expression<charT,..> c'tors and assignments which take a textual regular expression as argument. (Maybe this defintion is incomplete, but we can work on that). Also I see the existence of boost::regbase::use_except and boost::regbase::failbit I don't see how to use them in a way to enable/disable exceptions in regular expressions, dispite probably the activation of the general BOOST_NO_EXCEPTIONS (Shame on me!). Question: It seems, that boost::regbase::use_except is always active, because it is or'ed to the flags arguments in every(?) c'tor or assignment of reg_expression. Is that true? If that is true: Why does the flag regbase::use_except (officially) exist? Lets assume, that throwing boost::bad_expression is a general policy (I can live with that), it would be **very** nice to have at least one (probably static) member function, which takes a textual regular expression and an optional bunch of regbase flags as arguments and returns a bool, which simply returns true in case of a valid expression, otherwise false. What do you think of that? Of course I could write my own wrapper, which internally uses a try/catch(boost::bad_expression) block, but that is not a very nice programming style I think, according to the general guideline: "If you **can** handle a problem locally, do should do that". Thank you for your help, Daniel Spangenberg P.S.: Please forgive me, if I obviously overlooked some already present feature of regex! _______________________________________________ Unsubscribe & other changes: http://lists.boost.org/mailman/listinfo.cgi/boost
