diff --git a/src/grammars.hpp b/src/grammars.hpp
index 02d6666..253a16a 100644
--- a/src/grammars.hpp
+++ b/src/grammars.hpp
@@ -74,7 +74,7 @@
     command_names_table()
     {
         boost::mpl::for_each<CommandTypes, boost::type<boost::mpl::_>>([this](auto cmd) {
-            add(commandNamesVisitor()(cmd), decltype(help_::m_cmd)(cmd));
+            add(commandNamesVisitor(cmd), decltype(help_::m_cmd)(cmd));
         });
     }
 } const command_names;