Function greeting

test/snippets.cpp:263–279

tag::snippet_strings_5[]

// tag::snippet_strings_5[]
string greeting( string_view first_name, string_view last_name )
{
    const char hello[] = "Hello, ";
    const std::size_t sz = first_name.size() + last_name.size() + sizeof(hello) + 1;

    string js;
    js.reserve(sz);

    char* p = std::copy( hello, hello + sizeof(hello) - 1, js.data() );
    p = std::copy( first_name.begin(), first_name.end(), p );
    *p++ = ' ';
    p = std::copy( last_name.begin(), last_name.end(), p );
    *p++ = '!';

    js.grow( sz );
    return js;
}
// end::snippet_strings_5[]

void