Restarted the production of the app

libs/CLI11/examples/shapes.cpp

@@ -0,0 +1,56 @@
+// Copyright (c) 2017-2022, University of Cincinnati, developed by Henry Schreiner
+// under NSF AWARD 1414736 and by the respective contributors.
+// All rights reserved.
+//
+// SPDX-License-Identifier: BSD-3-Clause
+
+#include <CLI/CLI.hpp>
+#include <iostream>
+#include <vector>
+
+int main(int argc, char **argv) {
+
+    CLI::App app("load shapes");
+
+    app.set_help_all_flag("--help-all");
+    auto *circle = app.add_subcommand("circle", "draw a circle")->immediate_callback();
+    double radius{0.0};
+    int circle_counter{0};
+    circle->callback([&radius, &circle_counter] {
+        ++circle_counter;
+        std::cout << "circle" << circle_counter << " with radius " << radius << std::endl;
+    });
+
+    circle->add_option("radius", radius, "the radius of the circle")->required();
+
+    auto *rect = app.add_subcommand("rectangle", "draw a rectangle")->immediate_callback();
+    double edge1{0.0};
+    double edge2{0.0};
+    int rect_counter{0};
+    rect->callback([&edge1, &edge2, &rect_counter] {
+        ++rect_counter;
+        if(edge2 == 0) {
+            edge2 = edge1;
+        }
+        std::cout << "rectangle" << rect_counter << " with edges [" << edge1 << ',' << edge2 << "]" << std::endl;
+        edge2 = 0;
+    });
+
+    rect->add_option("edge1", edge1, "the first edge length of the rectangle")->required();
+    rect->add_option("edge2", edge2, "the second edge length of the rectangle");
+
+    auto *tri = app.add_subcommand("triangle", "draw a rectangle")->immediate_callback();
+    std::vector<double> sides;
+    int tri_counter = 0;
+    tri->callback([&sides, &tri_counter] {
+        ++tri_counter;
+
+        std::cout << "triangle" << tri_counter << " with sides [" << CLI::detail::join(sides) << "]" << std::endl;
+    });
+
+    tri->add_option("sides", sides, "the side lengths of the triangle");
+
+    CLI11_PARSE(app, argc, argv);
+
+    return 0;
+}