static std::size_t length( const char_type* s ); (constexpr since C++17) Returns the length of the character sequence pointed to by s, that is, the position of the terminating null character (char_type()). See CharTraits for the general requirements on character traits for X::length...
std::char_traits staticintcompare(constchar_type*s1,constchar_type*s2, std::size_tcount); (constexpr since C++17) Compares the firstcountcharacters of the character stringss1ands2. The comparison is done lexicographically. Ifcountis zero, strings are considered equal. ...
C++ 字符串库 std::char_traits static void assign( char_type& c1, const char_type& c2 ); (1) (C++11 起为 noexcept)(C++17 起为 constexpr) static char_type* assign( char_type* ptr, std::size_t count, char_type c2 ); (...
char16_t std::uint_least16_t std::streamoff std::u16streampos std::mbstate_t char_traits<char32_t> (C++11) char32_t std::uint_least32_t std::streamoff std::u32streampos std::mbstate_t 大char_traits类模板满足CharTraits...
如果fmt是std::chars_format::hex,那么不允许前缀 "0x" 或 "0X"(字符串 "0x123" 分析为值 "0" 和未分析的剩余 "x123")。 不忽略前导空白。 任何情况下,按照std::round_to_nearest舍入后,结果值是最多两个最接近匹配模式的字符串的值的浮点数之一。
std::char_traits<wchar_t>===<WEOF std::char_traits<char16_t>(C++11)===<非法 UTF-16 编码单元 std::char_traits<char32_t>(C++11)===<非法 UTF-32 编码单元 std::char_traits<char8_t>(C++20)===<非法 UTF-8 编码单元 char_traits类模板的标准特化满足字符特征(CharTraits)的要求。
char *begin, char *end, std::basic_string_view<std::byte> const &value) char *begin, char *end, bytes_view const &value) { auto const budget{size_buffer(value)}; if (internal::cmp_less(end - begin, budget)) Expand All @@ -1009,7 +1009,7 @@ template<> struct string_traits<...
_traits<_Kty,_Ty,_Pr,_Alloc,false>>::find(const std::basic_string<char16_t,std::char_traits<char16_t>,std::allocator<char16_t>> &) const': cannot convert argument 1 from 'const WCHAR *' to 'const std::basic_string<char16_t,std::char_traits<char16_t>,std::allocator<char16...
Traits::eq() 用于比较字符值。初始化字符串的有效长度是min(n, str.size() - pos)。如果pos > str.size(),此构造函数会抛出std::out_of_range异常。如果str中检查的任何字符都不是零或一,它会抛出std::invalid_argument异常。 类似于 (3),但使用CharT*而不是std::basic_string。等价于bitset(n == ...
std::tuple<int,bool, string> t = std::forward_as_tuple(11,true,"ok"); Printer<std::tuple<int,bool, string>>::log(t);return1; } 执行结果: int:11 bool:1 class std::basic_string<char,struct std::char_traits<char>,class std::allocator<char> >:ok ...