diff --git a/src/convert/patternreplacer.h b/src/convert/patternreplacer.h
index 39dba08..8dd2bfd 100644
--- a/src/convert/patternreplacer.h
+++ b/src/convert/patternreplacer.h
@@ -5,7 +5,7 @@
  */
 
 /*
- * Copyright (c) 2018-2021, Tomasz Sowa
+ * Copyright (c) 2018-2022, Tomasz Sowa
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -132,7 +132,7 @@ private:
 						const CharType * index_start_str = &pattern[i+1];
 						const CharType * after_str;
 						bool was_overflow;
-						unsigned long index = Toul(index_start_str, 10, &after_str, &was_overflow, false);
+						unsigned long index = to_ul(index_start_str, 10, &after_str, &was_overflow, false);
 
 						if( !was_overflow && after_str > index_start_str && (size_t)index < params.size() )
 						{