Example: typemeta_StaticString

C++ example source code:

/* +------------------------------------------------------------------------+
   |                     Mobile Robot Programming Toolkit (MRPT)            |
   |                          https://www.mrpt.org/                         |
   |                                                                        |
   | Copyright (c) 2005-2021, Individual contributors, see AUTHORS file     |
   | See: https://www.mrpt.org/Authors - All rights reserved.               |
   | Released under BSD License. See: https://www.mrpt.org/License          |
   +------------------------------------------------------------------------+ */
#include <mrpt/typemeta/static_string.h>

#include <iostream>

void Test_StaticString()
{
    using namespace std;
    using namespace mrpt::typemeta;

    constexpr string_literal<3> s = "foo";
    cout << "string_literal<3>=" << s << endl;

    constexpr auto a = literal("foo");
    constexpr auto b = literal("bar");
    // In GCC7 this can be "constexpr", but it fails in MSVC 2017 (!)
    auto ab = a + b;
    cout << "a=" << a << endl;
    cout << "b=" << b << endl;
    cout << "a+b=" << ab << endl;

    static_assert(ab.size() == 6, "***");
    cout << "(a+b).size()=" << ab.size() << endl;
    cout << "(a+b)[0]=" << ab[0] << endl;
    cout << "(a+b)[5]=" << ab[5] << endl;
}

#include <mrpt/typemeta/num_to_string.h>

#include <iostream>

void Test_StaticNum2Str()
{
    using namespace std;
    using namespace mrpt::typemeta;

    constexpr auto n42 = num_to_string<42>::value;
    constexpr auto n9999 = num_to_string<9999>::value;
    cout << "42 as string=" << n42 << endl;
    cout << "9999 as string=" << n9999 << endl;
}

int main(int argc, char** argv)
{
    try
    {
        Test_StaticString();
        return 0;
    }
    catch (const std::exception& e)
    {
        std::cerr << "MRPT error: " << e.what() << std::endl;
        return -1;
    }
}