diff --git a/src/json.hpp b/src/json.hpp
index e20ab71d..9a04a62b 100644
--- a/src/json.hpp
+++ b/src/json.hpp
@@ -14492,7 +14492,7 @@ struct hash<nlohmann::json>
 
 /// specialization for std::less<value_t>
 template<>
-struct less<::nlohmann::detail::value_t>
+struct less<nlohmann::detail::value_t>
 {
     /*!
     @brief compare two value_t enum values