diff --git a/src/convert/patternreplacer.h b/src/convert/patternreplacer.h
index 65569f0..02d73b4 100644
--- a/src/convert/patternreplacer.h
+++ b/src/convert/patternreplacer.h
@@ -5,7 +5,7 @@
  */
 
 /*
- * Copyright (c) 2018, Tomasz Sowa
+ * Copyright (c) 2018-2021, Tomasz Sowa
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -86,7 +86,7 @@ private:
 		params.clear();
 		AddParams(types...);
 		ReplacePattern(pattern);
-		buffer.to_string(output_string);
+		buffer.to_str(output_string);
 
 		params.clear();
 		buffer.clear();
@@ -104,7 +104,7 @@ private:
 	{
 		buffer.clear();
 		buffer << type;
-		buffer.to_string(temp_str);
+		buffer.to_str(temp_str);
 		params.push_back(temp_str);
 		temp_str.clear();