Speaking of mapping constants, I recently fixed this bug in refdoc/presentation/make_html.pike:
mapping lay = ([ ... "dochead" : "<dt>", "_dochead" : "</dt>\n", ... "dochead" : "\n<dt style='font-family: sans-serif'>", "_dochead" : "</dt>\n", ... ]);
Ought to give a warning, I think. Or maybe even an error.