From cppreference.com
constexprsize_typemax_size()constnoexcept;(since C++17)The largest possible number of char-like objects that can be referred to by a basic_string_view.
Return value
Maximum number of characters.
Complexity
Constant.
Example
Run this code
#include<cstdint>#include<iostream>#include<limits>#include<string_view>intmain(){std::cout<<std::numeric_limits<std::int64_t>::max()<<" <- numeric_limits<int64_t>::max()\n"<<std::string_view{}.max_size()<<" <- string_view::max_size()\n"<<std::basic_string_view<char>{}.max_size()<<" <- basic_string_view<char>::max_size()\n"<<std::basic_string_view<char16_t>{}.max_size()<<" <- basic_string_view<char16_t>::max_size()\n"<<std::wstring_view{}.max_size()<<" <- wstring_view::max_size()\n"<<std::basic_string_view<char32_t>{}.max_size()<<" <- basic_string_view<char32_t>::max_size()\n";}Possible output:
9223372036854775807 <- numeric_limits<int64_t>::max() 4611686018427387899 <- string_view::max_size() 4611686018427387899 <- basic_string_view<char>::max_size() 2305843009213693949 <- basic_string_view<char16_t>::max_size() 1152921504606846974 <- wstring_view::max_size() 1152921504606846974 <- basic_string_view<char32_t>::max_size() See also
returns the number of characters
(public member function)
checks whether the view is empty
(public member function)
returns the maximum number of characters
(public member function of std::basic_string<CharT,Traits,Allocator>)