diff --git a/src/string_func.h b/src/string_func.h
--- a/src/string_func.h
+++ b/src/string_func.h
@@ -58,6 +58,7 @@ void StrTrimInPlace(std::string &str);
 
 [[nodiscard]] int StrCompareIgnoreCase(const std::string_view str1, const std::string_view str2);
 [[nodiscard]] bool StrEqualsIgnoreCase(const std::string_view str1, const std::string_view str2);
+[[nodiscard]] int StrNaturalCompare(std::string_view s1, std::string_view s2, bool ignore_garbage_at_front = false);
 
 /**
  * Check if a string buffer is empty.
@@ -277,6 +278,4 @@ static inline bool IsWhitespace(WChar c)
 char *strcasestr(const char *haystack, const char *needle);
 #endif /* strcasestr is available */
 
-int strnatcmp(const char *s1, const char *s2, bool ignore_garbage_at_front = false);
-
 #endif /* STRING_FUNC_H */