"Angus Leeming" <angus.leeming@btopenworld.com> wrote in message news:ch7h3d$466$1@sea.gmane.org...
I'm trying to ascertain whether a given class is, or is derived from, std::basic_ostream, but I've ground to a halt.
The attached file ios_traits.hpp is from my iostreams library currently under review. It contains MPL-compatible metafunctions is_istream, is_ostream, is_iostream and is_streambuf to test whether a given type is the same as or derived from the corresponding standard library template. It has served me well, but I'd be happy to have others examine it. Note that it is fairly common for a stream to derive privately from basic_streambuf; with the current implementation, testing such a stream using is_streambuf causes a compiler error. Jonathan begin 666 ios_traits.hpp M+R\@*$,I($-O<'ER:6=H="!*;VYA=&AA;B!4=7)K86YI<R R,# S+@T*+R\@ M1&ES=')I8G5T960@=6YD97(@=&AE($)O;W-T(%-O9G1W87)E($QI8V5N<V4L M(%9E<G-I;VX@,2XP+B H4V5E(&%C8V]M<&%N>6EN9PT*+R\@9FEL92!,24-% M3E-%7S%?,"YT>'0@;W(@8V]P>2!A="!H='1P.B\O=W=W+F)O;W-T+F]R9R], M24-%3E-%7S%?,"YT>'0N*0T*#0HC:69N9&5F($)/3U-47TE/7TE/4U]44D%) M5%-?2%!07TE.0TQ51$5$#0HC9&5F:6YE($)/3U-47TE/7TE/4U]44D%)5%-? 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