diff options
Diffstat (limited to 'indra/llcommon/stringize.h')
-rw-r--r-- | indra/llcommon/stringize.h | 73 |
1 files changed, 44 insertions, 29 deletions
diff --git a/indra/llcommon/stringize.h b/indra/llcommon/stringize.h index 1b2958020f..6399547f5e 100644 --- a/indra/llcommon/stringize.h +++ b/indra/llcommon/stringize.h @@ -13,6 +13,7 @@ #define LL_STRINGIZE_H #include <sstream> +#include <boost/lambda/lambda.hpp> /** * stringize(item) encapsulates an idiom we use constantly, using @@ -28,6 +29,17 @@ std::string stringize(const T& item) } /** + * stringize_f(functor) + */ +template <typename Functor> +std::string stringize_f(Functor const & f) +{ + std::ostringstream out; + f(out); + return out.str(); +} + +/** * STRINGIZE(item1 << item2 << item3 ...) effectively expands to the * following: * @code @@ -36,40 +48,43 @@ std::string stringize(const T& item) * return out.str(); * @endcode */ -#define STRINGIZE(EXPRESSION) (static_cast<std::ostringstream&>(Stringize() << EXPRESSION).str()) +#define STRINGIZE(EXPRESSION) (stringize_f(boost::lambda::_1 << EXPRESSION)) + /** - * Helper class for STRINGIZE() macro. Ideally the body of - * STRINGIZE(EXPRESSION) would look something like this: + * destringize(str) + * defined for symmetry with stringize + * *NOTE - this has distinct behavior from boost::lexical_cast<T> regarding + * leading/trailing whitespace and handling of bad_lexical_cast exceptions + */ +template <typename T> +T destringize(std::string const & str) +{ + T val; + std::istringstream in(str); + in >> val; + return val; +} + +/** + * destringize_f(str, functor) + */ +template <typename Functor> +void destringize_f(std::string const & str, Functor const & f) +{ + std::istringstream in(str); + f(in); +} + +/** + * DESTRINGIZE(str, item1 >> item2 >> item3 ...) effectively expands to the + * following: * @code - * (std::ostringstream() << EXPRESSION).str() + * std::istringstream in(str); + * in >> item1 >> item2 >> item3 ... ; * @endcode - * That doesn't work because each of the relevant operator<<() functions - * accepts a non-const std::ostream&, to which you can't pass a temp instance - * of std::ostringstream. Stringize plays the necessary const tricks to make - * the whole thing work. */ -class Stringize -{ -public: - /** - * This is the essence of Stringize. The leftmost << operator (the one - * coded in the STRINGIZE() macro) engages this operator<<() const method - * on the temp Stringize instance. Every other << operator (ones embedded - * in EXPRESSION) simply sees the std::ostream& returned by the first one. - * - * Finally, the STRINGIZE() macro downcasts that std::ostream& to - * std::ostringstream&. - */ - template <typename T> - std::ostream& operator<<(const T& item) const - { - mOut << item; - return mOut; - } +#define DESTRINGIZE(STR, EXPRESSION) (destringize_f((STR), (boost::lambda::_1 >> EXPRESSION))) -private: - mutable std::ostringstream mOut; -}; #endif /* ! defined(LL_STRINGIZE_H) */ |