Added additional samples and fixed parse_known_args API

include/argparse/argparse.hpp

@@ -1200,8 +1200,8 @@ public:
    * @throws std::runtime_error in case of any invalid argument
    */
   // NOLINTNEXTLINE(cppcoreguidelines-avoid-c-arrays)
-  void parse_known_args(int argc, const char *const argv[]) {
+  auto parse_known_args(int argc, const char *const argv[]) {
-    parse_known_args({argv, argv + argc});
+    return parse_known_args({argv, argv + argc});
   }
 
   /* Getter for options with default values.

samples/CMakeLists.txt

@@ -36,4 +36,11 @@ add_sample(is_used)
 add_sample(joining_repeated_optional_arguments)
 add_sample(repeating_argument_to_increase_value)
 add_sample(negative_numbers)
+add_sample(description_epilog_metavar)
+add_sample(list_of_arguments)
+add_sample(compound_arguments)
+add_sample(gathering_remaining_arguments)
 add_sample(subcommands)
+add_sample(parse_known_args)
+add_sample(custom_prefix_characters)
+add_sample(custom_assignment_characters)

samples/compound_arguments.cpp

@@ -0,0 +1,36 @@
+#include <argparse/argparse.hpp>
+
+int main(int argc, char *argv[]) {
+  argparse::ArgumentParser program("test");
+
+  program.add_argument("-a").default_value(false).implicit_value(true);
+
+  program.add_argument("-b").default_value(false).implicit_value(true);
+
+  program.add_argument("-c")
+      .nargs(2)
+      .default_value(std::vector<float>{0.0f, 0.0f})
+      .scan<'g', float>();
+
+  try {
+    program.parse_args(argc, argv); // Example: ./main -abc 1.95 2.47
+  } catch (const std::runtime_error &err) {
+    std::cerr << err.what() << std::endl;
+    std::cerr << program;
+    std::exit(1);
+  }
+
+  auto a = program.get<bool>("-a");               // true
+  auto b = program.get<bool>("-b");               // true
+  auto c = program.get<std::vector<float>>("-c"); // {1.95, 2.47}
+
+  std::cout << "a: " << std::boolalpha << a << "\n";
+  std::cout << "b: " << b << "\n";
+  if (!c.empty()) {
+    std::cout << "c: ";
+    for (auto &v : c) {
+      std::cout << v << " ";
+    }
+    std::cout << std::endl;
+  }
+}

samples/custom_assignment_characters.cpp

@@ -0,0 +1,27 @@
+#include <argparse/argparse.hpp>
+#include <cassert>
+
+int main(int argc, char *argv[]) {
+  argparse::ArgumentParser program("test");
+  program.set_prefix_chars("-+/");
+  program.set_assign_chars("=:");
+
+  program.add_argument("--foo");
+  program.add_argument("/B");
+
+  try {
+    program.parse_args(argc, argv);
+  } catch (const std::runtime_error &err) {
+    std::cerr << err.what() << std::endl;
+    std::cerr << program;
+    std::exit(1);
+  }
+
+  if (program.is_used("--foo")) {
+    std::cout << "--foo : " << program.get("--foo") << "\n";
+  }
+
+  if (program.is_used("/B")) {
+    std::cout << "/B    : " << program.get("/B") << "\n";
+  }
+}

samples/custom_prefix_characters.cpp

@@ -0,0 +1,31 @@
+#include <argparse/argparse.hpp>
+#include <cassert>
+
+int main(int argc, char *argv[]) {
+  argparse::ArgumentParser program("test");
+  program.set_prefix_chars("-+/");
+
+  program.add_argument("+f");
+  program.add_argument("--bar");
+  program.add_argument("/foo");
+
+  try {
+    program.parse_args(argc, argv);
+  } catch (const std::runtime_error &err) {
+    std::cerr << err.what() << std::endl;
+    std::cerr << program;
+    std::exit(1);
+  }
+
+  if (program.is_used("+f")) {
+    std::cout << "+f    : " << program.get("+f") << "\n";
+  }
+
+  if (program.is_used("--bar")) {
+    std::cout << "--bar : " << program.get("--bar") << "\n";
+  }
+
+  if (program.is_used("/foo")) {
+    std::cout << "/foo  : " << program.get("/foo") << "\n";
+  }
+}

samples/description_epilog_metavar.cpp

@@ -0,0 +1,17 @@
+#include <argparse/argparse.hpp>
+
+int main(int argc, char *argv[]) {
+  argparse::ArgumentParser program("main");
+  program.add_argument("thing").help("Thing to use.").metavar("THING");
+  program.add_argument("--member")
+      .help("The alias for the member to pass to.")
+      .metavar("ALIAS");
+  program.add_argument("--verbose").default_value(false).implicit_value(true);
+
+  program.add_description("Forward a thing to the next member.");
+  program.add_epilog("Possible things include betingalw, chiz, and res.");
+
+  program.parse_args(argc, argv);
+
+  std::cout << program << std::endl;
+}

samples/gathering_remaining_arguments.cpp

@@ -0,0 +1,24 @@
+#include <argparse/argparse.hpp>
+
+int main(int argc, char *argv[]) {
+  argparse::ArgumentParser program("compiler");
+
+  program.add_argument("files").remaining();
+
+  try {
+    program.parse_args(argc, argv);
+  } catch (const std::runtime_error &err) {
+    std::cerr << err.what() << std::endl;
+    std::cerr << program;
+    std::exit(1);
+  }
+
+  try {
+    auto files = program.get<std::vector<std::string>>("files");
+    std::cout << files.size() << " files provided" << std::endl;
+    for (auto &file : files)
+      std::cout << file << std::endl;
+  } catch (std::logic_error &e) {
+    std::cout << "No files provided" << std::endl;
+  }
+}

samples/list_of_arguments.cpp

@@ -0,0 +1,30 @@
+#include <argparse/argparse.hpp>
+
+int main(int argc, char *argv[]) {
+
+  argparse::ArgumentParser program("main");
+
+  program.add_argument("--input_files")
+      .help("The list of input files")
+      .nargs(2);
+
+  try {
+    program.parse_args(
+        argc, argv); // Example: ./main --input_files config.yml System.xml
+  } catch (const std::runtime_error &err) {
+    std::cerr << err.what() << std::endl;
+    std::cerr << program;
+    std::exit(1);
+  }
+
+  auto files = program.get<std::vector<std::string>>(
+      "--input_files"); // {"config.yml", "System.xml"}
+
+  if (!files.empty()) {
+    std::cout << "Files: ";
+    for (auto &file : files) {
+      std::cout << file << " ";
+    }
+    std::cout << std::endl;
+  }
+}

samples/parse_known_args.cpp

@@ -0,0 +1,26 @@
+#include <argparse/argparse.hpp>
+#include <cassert>
+
+int main(int argc, char *argv[]) {
+  argparse::ArgumentParser program("test");
+  program.add_argument("--foo").implicit_value(true).default_value(false);
+  program.add_argument("bar");
+
+  auto unknown_args = program.parse_known_args(argc, argv);
+
+  if (program.is_used("--foo")) {
+    std::cout << "--foo        : " << program.get<bool>("--foo") << "\n";
+  }
+
+  if (program.is_used("bar")) {
+    std::cout << "bar          : " << program.get<std::string>("bar") << "\n";
+  }
+
+  if (!unknown_args.empty()) {
+    std::cout << "Unknown args : ";
+    for (const auto &u : unknown_args) {
+      std::cout << u << " ";
+    }
+    std::cout << std::endl;
+  }
+}