add a cmdline example

cmdline/CMakeLists.txt

@@ -16,4 +16,5 @@
 cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
 
 add_subdirectory(src)
+add_subdirectory(examples)
 add_subdirectory(test)

cmdline/examples/CMakeLists.txt

+# © 2020 ETH Zurich, Mechanics and Materials Lab
+# © 2020 California Institute of Technology
+#
+# 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.
+
+cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
+
+add_executable(${PROJECT_NAME}-CmdLineExample
+               ./Example.cc
+)
+
+target_link_libraries(${PROJECT_NAME}-CmdLineExample
+                      PRIVATE ${PROJECT_NAME}::cmdline
+)

cmdline/examples/Example.cc

+// © 2020 ETH Zurich, Mechanics and Materials Lab
+//
+// 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 <ae108/cmdline/CommandLineOptionParser.h>
+#include <iostream>
+
+int main(const int argc, const char *const *const argv) {
+  namespace cmdline = ae108::cmdline;
+
+  auto enable_greeting = bool{false};
+  cmdline::CommandLineOptionParser(std::cerr)
+      .withOption("enable_greeting,g", "Print a greeting.", &enable_greeting)
+      .parse(argc, argv);
+
+  if (enable_greeting) {
+    std::cout << "Hello world!" << std::endl;
+  }
+}