Hi Hans, there is \setbox missing before the \b_assign_width\emptybox assignments. \setvalue{\??dimensionwidth }#value#dimension#content#extra{\setbox\b_assign_width\hbox{#content}#dimension\wd\b_assign_width\b_assign_width\emptybox} \setvalue{\??dimensionwidth\v!fit }#value#dimension#content#extra{\setbox\b_assign_width\hbox{#content}#dimension\wd\b_assign_width\b_assign_width\emptybox} \setvalue{\??dimensionwidth\v!broad }#value#dimension#content#extra{\setbox\b_assign_width\hbox{#content}#dimension\dimexpr\wd\b_assign_width+#extra\relax\b_assign_width\emptybox} Wolfgang