The library is fairly small and can be seen as an extension to boost.functional. Therefore the review is a fast-track review.
Documentation mentions two overloaded functions: std::size_t hash_value(std::string); std::size_t hash_value(std::wstring); while hash.hpp actually delivers one template function: template <class E, class T, class A> std::size_t hash_value(std::basic_string<E, T, A> const& v); I'd prefer documentation updated. Overall I consider this functionality desired in Boost; I also like design (single template class hash calling overloaded hash_function). I implemented similar functionality in the past (as many of us did, I'm pretty sure), and this design is something I would not be ashamed of, if I wrote it myself. I would however consider implementing most overloads of hash_value inline; I know that from technical perspective compiler is free to inline function call anyway, but putting implementation in header will make optimizer job easier and more obvious to user. B. -- Bronek Kozicki brok@rubikon.pl http://b.kozicki.pl/