A bug in boost.lexical_cast 1.30

When lexical_cast used under VC, and the option "Treat wchar_t as Build-in Type" is off The following code will cause compile error: int main(int argc, char * argv[]) { string str("10"); unsigned short n = lexical_cast<unsigned short>(str); return 0; } Because in lexical_cast::detail::widest_char, treat unsigned short as wchar_t!! -- /*******************/ ×ÔÓÉ£šliberty£©ÎÞ·ÇŸÍÊÇÕâÑùÒ»ÖÖ³Ðŵ£ºÃ¿žöÈËœ«»áµÃµœÒ»ÖÖ±£ÕÏ£¬±£ÕÏÎÒÃÇ¿ÉÒÔÓë ÈšÍþ¡¢¶àÊý¡¢Á÷Ë׌°ÓßÂÛµÄÓ°ÏìÏ࿹ºâ¡£ /*******************/