diff --git a/modules/core/include/opencv2/core/operations.hpp b/modules/core/include/opencv2/core/operations.hpp
index 954604a9d..5895e4c4a 100644
--- a/modules/core/include/opencv2/core/operations.hpp
+++ b/modules/core/include/opencv2/core/operations.hpp
@@ -394,7 +394,9 @@ template<typename _Tp> static inline _Tp randu()
   return (_Tp)theRNG();
 }
 
+///////////////////////////////// Formatted string generation /////////////////////////////////
 
+CV_EXPORTS String format( const char* fmt, ... );
 
 ///////////////////////////////// Formatted output of cv::Mat /////////////////////////////////