std::basic_string<CharT,Traits,Allocator>::basic_string

#include <cassert>
#include <cctype>
#include <iomanip>
#include <iostream>
#include <iterator>
#include <string>

int main()
{
    std::cout << "1) string(); ";
    std::string s1;
    assert(s1.empty() && (s1.length() == 0) && (s1.size() == 0));
    std::cout << "s1.capacity(): " << s1.capacity() << '\n'; //  
    
    std::cout << "2) string(size_type count, CharT ch): ";
    std::string s2(4, '=');
    std::cout << std::quoted(s2) << '\n'; // "===="
    
    std::cout << "3) string(const string& other, size_type pos, size_type count): ";
    std::string const other3("");
    std::string s3(other3, 0, other3.length() - 1);
    std::cout << std::quoted(s3) << '\n'; // ""
    
    std::cout << "4) string(const string& other, size_type pos): ";
    std::string const other4("Mutatis Mutandis");
    std::string s4(other4, 8);
    std::cout << std::quoted(s4) << '\n'; // "Mutandis",   [8, 16)
    
    std::cout << "5) string(CharT const* s, size_type count): ";
    std::string s5("C-style", 7);
    std::cout << std::quoted(s5) << '\n'; // "C-style",   [0, 7)
    
    std::cout << "6) string(CharT const* s): ";
    std::string s6("\0  ");
    std::cout << std::quoted(s6) << '\n'; // ""
    
    std::cout << "7) string(InputIt first, InputIt last): ";
    char mutable_c_str[] = "another C-style string";
    std::string s7(std::begin(mutable_c_str) + 8, std::end(mutable_c_str) - 1);
    std::cout << std::quoted(s7) << '\n'; // "    C"
    
    std::cout << "8) string(string&): ";
    std::string const other8("");
    std::string s8(other8);
    std::cout << std::quoted(s8) << '\n'; // ""
    
    std::cout << "9) string(string&&): ";
    std::string s9(std::string("++  ") + std::string(""));
    std::cout << std::quoted(s9) << '\n'; // "++  "
    
    std::cout << "a) string(std::initializer_list<CharT>): ";
    std::string sa({'C', '-', 's', 't', 'y', 'l', 'e'});
    std::cout << std::quoted(sa) << '\n'; // "C-style"
    
    //  C++11    string(InputIt first, InputIt last)
    // [ InputIt = int],    *  *
    // string(size_type count, CharT ch).
    //  C++11  InputIt      :
    std::cout << "b) string(size_type count, CharT ch) : ";
    std::string sb(3, std::toupper('a'));
    std::cout << std::quoted(sb) << '\n'; // "AAA"
    
    //  std::string sc(nullptr); //  C++23:  std::logic_error
                                 //   C++23:  ,
                                 //   (12)
//  std::string sc(0); //  ,   ,   0 
                       //   

    auto const range = {0x43, 43, 43};
#ifdef __cpp_lib_containers_ranges
    std::string sc(std::from_range, range); //   (13)
    std::cout << "c) string(std::from_range, range) : ";
#else
    std::string sc(range.begin(), range.end()); //    (7)
    std::cout << "c) string(range.begin(), range.end()) : ";
#endif
    std::cout << std::quoted(sc) << '\n'; // "C++"
}