Maximum length of a std::basic_string<_CharT> string
问题 I was wondering how one can fix an upper limit for the length of a string (in C++) for a given platform. I scrutinized a lot of libraries, and most of them define it arbitrarily. The GNU C++ STL (the one with experimental C++0x features) has quite a definition: size_t npos = size_t(-1); /*!< The maximum value that can be stored in a variable of type size_t */ size_t _S_max_len = ((npos - sizeof(_Rep_base))/sizeof(_CharT) - 1) / 4; /*!< Where _CharT is a template parameter; _Rep_base is a