--- a/src/html.h	Fri Feb 27 14:38:01 2026 +0100
+++ b/src/html.h	Thu Mar 12 12:00:50 2026 +0100
@@ -37,6 +37,7 @@
     static constexpr unsigned max_external_indentation = max_indentation - 4;
     static constexpr unsigned columns = 53;
 
+    int set_output(std::string const &path);
     void open(bool fragment, unsigned char fragment_indent = 0);
     void styles_and_script();
     void close(bool fragment);