/*

* Copyright (C) 2020-2026 MEmilio

*

* Authors: Rene Schmieding

*

* Contact: Martin J. Kuehn <[email protected]>

*

* Licensed under the Apache License, Version 2.0 (the "License");

* you may not use this file except in compliance with the License.

* You may obtain a copy of the License at

*

* http://www.apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

*/

#include "memilio/io/cli.h"

int main(int argc, char** argv)

{

// Print a message if no arguments were given.

if (argc == 1) {

std::cout << "This is a small example on how to use the command line interface. "

"Use \"-h\" to show the help dialogue.\n";

}

// Create a parameter set for the CLI using the builder. This defines the (parameter) options that the user can set

// through the command line.

//

// To add() a parameter, you need to specify the name and type as template arguments, then pass an initial value.

// The type can sometimes be deduced from the initial value, so it can potentially be omitted.

// After the initial value you can set some optional fields of the parameter:

// - alias, which allows you to add a shorthand for setting values

// - description, which contains details on, e.g., what the parameter does and what values are accepted.

// - is_required, which makes the CLI check whether the parameter was set. If not, it exits with an error.

//

// As a general rule, use simple types! The more complicated the type, the more complex is the Json representation

// that the user has to input.

//

// Instead of using the builder, you can also define and pass a mio::ParameterSet as parameters.

// The main difference (for the CLI) is that the mio::ParameterSet uses struct names to "get" parameters, while

// the mio::cli::ParameterSet uses StringLiteral%s.

auto parameters = mio::cli::ParameterSetBuilder()

.add<"Name", std::vector<std::string>>({"FirstName", "LastName"},

{"n", "Enter your name as list of strings.", false})

.add<"Age">(0, {"a", "Enter your age."})

.add<"Greeting">(std::string("Hello World!"),

{.description = "Enter a custom greeting.", .is_required = false})

.build();

// Define some default options. This is an optional feature, that allows users to set some options in the given

// order as the first arguments, without specifying their name or alias.

auto default_options = std::vector<std::string>{"Name", "Age"};

// Parse command line arguments and/or set parameters. This next line as well as the following check on its result

// are required to use the CLI.

auto result = mio::command_line_interface(argv[0], argc, argv, parameters, default_options);

// Catch and print help output, printed options, and errors.

if (!result) {

std::cout << result.error().message(); // Do not use formatted_message().

return result.error().code().value(); // Use exit here when not used in main().

}

// Now, do something with the parameters!

// Note that the CLI only verifies that the user input is parsable, not plausible. If a parameter has certain value

// requirements, like "Age > 0", you must check this yourself.

std::cout << parameters.get<"Greeting">() << "\n"

<< "Name: ";

for (auto& name : parameters.get<"Name">()) {

std::cout << name << " ";

}

std::cout << "\n";

if (parameters.get<"Age">() > 0) {

std::cout << "Age: " << parameters.get<"Age">() << "\n";

}

return 0;

}