🚀 go-pugleaf

>>>>> On 18 Aug 92 02:08:40 GMT, mjm@spekl.as.arizona.edu (Mark McCaughrean) said:


Mark>      In the middle of an \halign, I want to use \noalign to set a
Mark> paragraph of text (say). I want this paragraph to have the same
Mark> width as the table I'm setting using \halign. How do I get TeX
Mark> to tell me what the width of the table is, i.e. the width of the
Mark> vertical box I'm currently in the middle of? (I don't want to use
Mark> \multispan, by the way: I want the exact width of the table, and 
Mark> I don't want to have to know how many columns to span).

Mark>      I figured I could make a \setbox with an \hrule inside it,
Mark> hoping the \hrule would be the width of the table, and that then
Mark> I could use \wd to get the width of the box. I can't get it to
Mark> work. Seems like TeX must know the width though, or does it only
Mark> work it out when it has digested the whole table?

TeX only `knows' the widths when it completes the table. This makes
what you want to do quite tricky, One possibilty is to put the whole
table in a \setbox0=\vbox{  } then you can get the final width of the
table using \wd0. You then `only' have to \lastbox your way back up
the table, removing one row at a time, back to the point where you
want to insert your vertical material, then you can 
\unvbox0 % the top half of the table
{\hsize=<saved value of \wd0>
your stuff}
\unvbox<where ever you have saved the bottom of the table>

David
--
                           David Carlisle
                                    JANET: carlisle@uk.ac.man.cs

                                    Computer Science Department
                                    Manchester University
                                    Oxford Road
                                    Manchester
                                    England
                                    M13 9PL