+% Output a cross-manual xref to #1. Used just above (twice).
+%
+% Only include the text "Section ``foo'' in" if the foo is neither
+% missing or Top. Thus, @xref{,,,foo,The Foo Manual} outputs simply
+% "see The Foo Manual", the idea being to refer to the whole manual.
+%
+% But, this being TeX, we can't easily compare our node name against the
+% string "Top" while ignoring the possible spaces before and after in
+% the input. By adding the arbitrary 7sp below, we make it much less
+% likely that a real node name would have the same width as "Top" (e.g.,
+% in a monospaced font). Hopefully it will never happen in practice.
+%
+% For the same basic reason, we retypeset the "Top" at every
+% reference, since the current font is indeterminate.
+%
+\def\crossmanualxref#1{%
+ \setbox\toprefbox = \hbox{Top\kern7sp}%
+ \setbox2 = \hbox{\ignorespaces \printedrefname \unskip \kern7sp}%
+ \ifdim \wd2 > 7sp % nonempty?
+ \ifdim \wd2 = \wd\toprefbox \else % same as Top?
+ \putwordSection{} ``\printedrefname'' \putwordin{}\space
+ \fi
+ \fi
+ #1%
+}
+