Moved help hack into cxxopts.

* Added some dumb, hacky code to cxxopts to hide groups with a certain name.
    * main.cpp now uses options.help() instead of specifying group names.

plip-sdl/cxxopts.hpp

@@ -54,6 +54,7 @@ THE SOFTWARE.
 
 namespace cxxopts
 {
+  const char *hidden_group = "--HIDDEN--";
   static constexpr struct {
     uint8_t major, minor, patch;
   } version = {
@@ -2042,7 +2043,10 @@ Options::generate_all_groups_help(String& result) const
 
   for (auto& group : m_help)
   {
-    all_groups.push_back(group.first);
+    // Very hacky, but more convenient than the alternative.
+    auto group_name = group.first;
+    if(group_name == hidden_group) continue;
+    all_groups.push_back(group_name);
   }
 
   generate_group_help(result, all_groups);

plip-sdl/main.cpp

@@ -16,7 +16,7 @@ cxxopts::ParseResult parseCmdLine(int argc, char **argv) {
         options.positional_help("CORE FILENAME")
                 .show_positional_help();
 
-        options.add_options("Hidden")
+        options.add_options(cxxopts::hidden_group)
                 ("c,core", "the core that should be used", cxxopts::value<std::string>())
                 ("f,filename", "the path to the ROM", cxxopts::value<std::string>())
                 ("positional", "", cxxopts::value<std::vector<std::string>>())
@@ -37,10 +37,7 @@ cxxopts::ParseResult parseCmdLine(int argc, char **argv) {
         if(result.count("help")) {
             // Icky hack. As far as I can tell there's no other way of hiding
             // unwanted/positional arguments using cxxopts.
-            std::cout << options.help({
-                "",
-                "Video"
-            }) << std::endl;
+            std::cout << options.help() << std::endl;
             exit(0);
         }