\divert(-1);
The semicolons are just to get GNU Emacs C mode to indent properly.

\define([C_TEXT], [text="#000000"]);
\define([C_LINK], [link="#0000EF"]);
\define([C_ALINK], [vlink="#51188E"]);
\define([C_VLINK], [alink="#FF0000"]);
\define([C_BG1], [bgcolor="#FFCC99"]);
\define([C_BG2], [bgcolor="#FF9900"]);
\define([C_BG3], [bgcolor="#CC6600"]);

\define([DO_HEADER],
        [\head([\title([GNU m4 - \defn([_TITLE])])],
               [\meta_if_set([AUTHOR])],
               [\meta_if_set([GENERATOR])],
               [\meta_if_set([KEYWORDS])],
               )]);

\define([DO_BODY],
        [\body([\C_TEXT \C_BG1 \C_LINK \C_VLINK \C_ALINK],
               [\table([cellpadding=5 width="100%"],
                       [\tr([align=left valign=bottom],
                            [\td([align=center valign=middle colspan="3" width="100%" \C_BG2],
                                 [\h1([GNU m4])],
                                 [\h2(\defn([_TITLE]))],
                                 )],
                            )],
                       [\tr([],
                            [\td([align=left valign=top width="15%" \C_BG2],
                                 [\include([menu.m4])],
                                 )],
                            [\td([align=left valign=top width="90%"],
                                 [$*],
                                 )],
                            )],
                       )],
               )]
    );

\define([DO_LAYOUT],
        [\doctype([html public "-//w3c//dtd html 4.0 transitional//en"])
\html([\DO_HEADER], [\DO_BODY([$*])])]
    );

\define([<], [&lt;]);
\define([>], [&gt;]);

\define([showlink], [\link($1, $1)]);
\define([mailto], [\link(mailto:$1, $1)]);


<!-- These macros are for having first a simple toc and later a more
thorough description of each item -->

\define([print_items], [\undivert(2)])

\define([item], [\li \link([[#]$1], [$2.])
\pushdef([_div], \divnum)\dnl
\divert(2)\dnl
\hr([align=center width="50%"])\dnl
\h2([\target([$1], [$2])])\dnl
$3\dnl
\divert(\_div)\dnl
\popdef([_div])\dnl
])