[common] add convenience LOG macro

dune/xt/common/timedlogging.hh

@@ -127,6 +127,15 @@ public:
 }; // class DefaultLogger
 
 
+/// \brief Convenience macro for enrivonments with a logger variable
+#ifdef LOG
+#  error Macro LOG already defined, open an issue at https://zivgitlab.uni-muenster.de/ag-ohlberger/dune-community/dune-xt/-/issues !
+#else
+#  define LOG(type)                                                                                                    \
+    if (logger.type##_enabled())                                                                                       \
+    logger.type()
+#endif
+
 /// \brief Convenience macro for classes with a logger member
 #ifdef LOG_
 #  error Macro LOG_ already defined, open an issue at https://zivgitlab.uni-muenster.de/ag-ohlberger/dune-community/dune-xt/-/issues !