Символьный литерал

#include <cstdint>
#include <iomanip>
#include <iostream>
#include <string_view>

template<typename CharT>
void dump(std::string_view s, const CharT c)
{
    const uint8_t* data{reinterpret_cast<const uint8_t*>(&c)};
    
    std::cout << s << " \t" << std::hex
              << std::uppercase << std::setfill('0');
    
    for (auto i{0U}; i != sizeof(CharT); ++i)
        std::cout << std::setw(2) << static_cast<unsigned>(data[i]) << ' ';
    
    std::cout << '\n';
}

void print(std::string_view str = "") { std::cout << str << '\n'; }

int main()
{
    print("Ordinary character literals:");
    char c1 = 'a'; dump("'a'", c1);
    char c2 = '\x2a'; dump("'*'", c2);

    print("\n" "Ordinary multi-character literals:");
    int mc1 = 'ab'; dump("'ab'", mc1);       // implementation-defined
    int mc2 = 'abc'; dump("'abc'", mc2);     // implementation-defined

    print("\n" "UTF-8 character literals:");
    char8_t C1 = u8'a'; dump("u8'a'", C1);
//  char8_t C2 = u8'¢'; dump("u8'¢'", C2);   // error: ¢ maps to two UTF-8 code units
//  char8_t C3 = u8'猫'; dump("u8'猫'", C3); // error: 猫 maps to three UTF-8 code units
//  char8_t C4 = u8'🍌'; dump("u8'🍌'", C4); // error: 🍌 maps to four UTF-8 code units

    print("\n" "UTF-16 character literals:");
    char16_t uc1 = u'a'; dump("u'a'", uc1);
    char16_t uc2 = u'¢'; dump("u'¢'", uc2);
    char16_t uc3 = u'猫'; dump("u'猫'", uc3);
//  char16_t uc4 = u'🍌'; dump("u'🍌'", uc4); // error: 🍌 maps to two UTF-16 code units

    print("\n" "UTF-32 character literals:");
    char32_t Uc1 = U'a'; dump("U'a'", Uc1);
    char32_t Uc2 = U'¢'; dump("U'¢'", Uc2);
    char32_t Uc3 = U'猫'; dump("U'猫'", Uc3);
    char32_t Uc4 = U'🍌'; dump("U'🍌'", Uc4);

    print("\n" "Wide character literals:");
    wchar_t wc1 = L'a'; dump("L'a'", wc1);
    wchar_t wc2 = L'¢'; dump("L'¢'", wc2);
    wchar_t wc3 = L'猫'; dump("L'猫'", wc3);
    wchar_t wc4 = L'🍌'; dump("L'🍌'", wc4);  // unsupported on Windows since C++23
}

Возможный вывод:

Ordinary character literals:
'a'         61 
'*'         2A 

Ordinary multi-character literals:
'ab'         62 61 00 00 
'abc'         63 62 61 00 

UTF-8 character literals:
u8'a'         61 

UTF-16 character literals:
u'a'         61 00 
u'¢'         A2 00 
u'猫'         2B 73 

UTF-32 character literals:
U'a'         61 00 00 00 
U'¢'         A2 00 00 00 
U'猫'         2B 73 00 00 
U'🍌'         4C F3 01 00 

Wide character literals:
L'a'         61 00 00 00 
L'¢'         A2 00 00 00 
L'猫'         2B 73 00 00 
L'🍌'         4C F3 01 00