Example: containers_params_by_name

This is another use of mrpt::containers::yaml for parameter passing.

Example output:

CALL #1 ================================
'threshold' is 3.05
Is 'altitude' set? 1
Is 'level' set? 0
Level is : 666
Dump of all params:
%YAML 1.2
---
altitude: 100
threshold: 3.05

CALL #2 ================================
'threshold' is 3.05
Is 'altitude' set? 1
Is 'level' set? 1
Level is : -1
Dump of all params:
%YAML 1.2
---
altitude: 100
level: -1
threshold: 3.05

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/containers/yaml.h>
#include <mrpt/core/exceptions.h>

#include <iostream>

using std::cout;
using std::endl;

void MyCoolFunction(const mrpt::containers::yaml& params)
{
    cout << "'threshold' is " << params["threshold"] << endl;
    cout << "Is 'altitude' set? " << params.has("altitude") << endl;
    cout << "Is 'level' set? " << params.has("level") << endl;
    cout << "Level is : " << params.getOrDefault("level", 666.0) << endl;
    cout << "Dump of all params:\n";
    params.printAsYAML(cout);
    cout << endl;
}

// ------------------------------------------------------
//              TestParameters
// ------------------------------------------------------
void TestParameters()
{
    {
        // Call #1
        cout << "CALL #1 ================================\n";
        mrpt::containers::yaml p;
        p["threshold"] = 3.05;
        p["altitude"] = 100;

        MyCoolFunction(p);
    }

    {
        // Call #2
        cout << "CALL #2 ================================\n";
        // clang-format off
        mrpt::containers::yaml p = mrpt::containers::yaml::Map(
            {
                {"threshold", 3.05},
                {"altitude", 100.0},
                {"level", -1.0}
            }
        );
        // clang-format on

        MyCoolFunction(p);
    }
}

int main()
{
    try
    {
        TestParameters();
        return 0;
    }
    catch (const std::exception& e)
    {
        std::cerr << "MRPT error: " << mrpt::exception_to_str(e) << std::endl;
        return -1;
    }
}