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// under NSF AWARD 1414736 and by the respective contributors.

// SPDX-License-Identifier: BSD-3-Clause

#include <CLI/CLI.hpp>

#include <iostream>

#include <string>

int main(int argc, char **argv) {

CLI::App app("test for positional arity");

auto *numbers = app.add_option_group("numbers", "specify key numbers");

auto *files = app.add_option_group("files", "specify files");

int num1{-1}, num2{-1};

numbers->add_option("num1", num1, "first number");

numbers->add_option("num2", num2, "second number");

std::string file1, file2;

files->add_option("file1", file1, "first file")->required();

files->add_option("file2", file2, "second file");

// set a pre parse callback that turns the numbers group on or off depending on the number of arguments

app.preparse_callback([numbers](std::size_t arity) {

if(arity <= 2) {

numbers->disabled();

} else {

numbers->disabled(false);

}

});

CLI11_PARSE(app, argc, argv);

if(num1 != -1)

std::cout << "Num1 = " << num1 << '\n';

if(num2 != -1)

std::cout << "Num2 = " << num2 << '\n';

std::cout << "File 1 = " << file1 << '\n';

if(!file2.empty()) {

std::cout << "File 2 = " << file2 << '\n';

}

return 0;

}