{

std::wstring_view wcstr_v = L"xyzzy";

char array[3] = {'B', 'a', 'r'};

std::string_view array_v(array, std::size(array));

std::string cppstr = "Foo";

std::string_view cppstr_v(&cppstr[0], cppstr.size());

std::cout << cppstr_v << '\n'

<< array_v << '\n'

<< wcstr_v.size() << '\n';

std::string_view v = "Hello, world";

v = v.substr(7);

std::cout << v << '\n';

std::string_view str_view("abcd");

auto begin = str_view.begin();

auto cbegin = str_view.cbegin();

std::cout << *begin << '\n';

std::cout << *cbegin << '\n';

std::cout << std::boolalpha << (begin == cbegin) << '\n';

std::cout << std::boolalpha << (*begin == *cbegin) << '\n';

std::string str = " trim me";

std::string_view v1 = str;

v1.remove_prefix(std::min(v.find_first_not_of(" "), v.size()));

std::cout << "String: '" << str << "'\n"

<< "View : '" << v1 << "'\n";

constexpr std::basic_string_view<char> source{"ABCDEF"};

std::array<char, 8> dest;

std::size_t count{}, pos{};

dest.fill('\0');

source.copy(dest.data(), count = 4); // pos = 0

std::cout << dest.data() << '\n'; // ABCD

dest.fill('\0');

source.copy(dest.data(), count = 4, pos = 1);

std::cout << dest.data() << '\n'; // BCDE

dest.fill('\0');

source.copy(dest.data(), count = 42, pos = 2); // ok, count -> 4

std::cout << dest.data() << '\n'; // CDEF

try

{

source.copy(dest.data(), count = 1, pos = 666); // throws: pos > size()

}

catch(std::out_of_range const& ex)

{

std::cout << ex.what() << '\n';

}

using namespace std::literals;

constexpr auto data{"ABCDEF"sv};

std::cout << data.substr() << '\n'; // ABCDEF

std::cout << data.substr(pos = 1) << '\n'; // BCDEF

std::cout << data.substr(pos = 2, count = 3) << '\n'; // CDE

std::cout << data.substr(pos = 4, count = 42) << '\n'; // EF

// count -> 2 == size() - pos == 6 - 4

const std::string_view str1("hello world");

std::string_view::const_reference refStr2 = str1.at(8);

std::cout << refStr2 << "\n";

char c[] = "Help";

using std::cout;

using std::endl;

cout << std::boolalpha;

std::string_view sv{c};

std::cout << sv.size() << std::endl;

cout << sv.back() << endl; // p

}