diff --git a/src/MeoAssistant/Controller.cpp b/src/MeoAssistant/Controller.cpp
index 5f3f587061..d9a7aa398d 100644
--- a/src/MeoAssistant/Controller.cpp
+++ b/src/MeoAssistant/Controller.cpp
@@ -422,7 +422,7 @@ std::optional<std::string> asst::Controller::call_command(const std::string& cmd
     Log.info("Call `", cmd, "` ret", exit_ret, ", cost", duration, "ms , stdout size:", pipe_data.size(),
              ", socket size:", sock_data.size());
     if (!pipe_data.empty() && pipe_data.size() < 4096) {
-        Log.trace("output:", Logger::separator("\n"), pipe_data);
+        Log.trace("output:", Logger::separator::newline, pipe_data);
     }
 
     if (!exit_ret) {
diff --git a/src/MeoAssistant/Logger.hpp b/src/MeoAssistant/Logger.hpp
index de391d843e..0612f30236 100644
--- a/src/MeoAssistant/Logger.hpp
+++ b/src/MeoAssistant/Logger.hpp
@@ -20,7 +20,16 @@ namespace asst
     public:
         struct separator
         {
-            separator(std::string_view str) : str(str) {}
+            separator() = default;
+            separator(std::string_view s) : str(s) {}
+            separator& operator=(std::string_view s) { str = s; }
+
+            static const separator none;
+            static const separator space;
+            static const separator tab;
+            static const separator newline;
+            static const separator comma;
+
             std::string_view str;
         };
 
@@ -238,8 +247,7 @@ namespace asst
         Stream& stream_put_line(Stream& s, First&& a0, Args&&... args)
         {
             stream_put<ToAnsi>(s, std::forward<First>(a0));
-            static const separator default_sep(" ");
-            stream_put_line_impl<ToAnsi, Stream, Args...>::apply(s, default_sep, std::forward<Args>(args)...);
+            stream_put_line_impl<ToAnsi, Stream, Args...>::apply(s, separator::space, std::forward<Args>(args)...);
             return s;
         }
 
@@ -251,6 +259,12 @@ namespace asst
         std::ofstream m_ofs;
     };
 
+    inline const Logger::separator Logger::separator::none;
+    inline const Logger::separator Logger::separator::space(" ");
+    inline const Logger::separator Logger::separator::tab("\t");
+    inline const Logger::separator Logger::separator::newline("\n");
+    inline const Logger::separator Logger::separator::comma(",");
+
     class LoggerAux
     {
     public: