Vertical alignment of arbitrary text

[Berend de Boer <berend@pobox.com>]

Hello Hans,

Is there a construct in ConTeXt to align two arbitrary pieces of text?
For example I wanted a chapter number and the contents of that chapter
to be aligned.

After much blood, sweat and tears I came up with this:

-------------------------------
\def\SimpleHead#1%
  {\vtop{\rightaligned{{\switchtobodyfont[36pt]\ }}\par
         \rightaligned{\startnarrower[3*left] #1\stopnarrower}}}

\def\myContents#1#2#3%
  {\sym{$\bullet$} {\bs #2}\par}

\newdimen\myheight
\newdimen\mydepth
\newbox\myboxA
\newbox\myboxB

\def\ContentsHead#1#2%
  {\setbox\myboxA=\vbox{\hsize=5cm
                    \startframedtext
                    [frame=off,background=screen,width=5cm]%
                    In this chapter:\par
                    \startalignment[right]
                    \placelist
                      [section]
                      [criterium=chapter,
                       alternative=command,
                       command=\myContents,
                       style=boldslanted,
                       align=left,
                       interaction=all,
                       before=,after=]%                 
                    \stopalignment
                    \stopframedtext}%
   \myheight=\ht\myboxA
   \mydepth=\dp\myboxA
   \ht\myboxA=0pt
   \advance\mydepth by \myheight
   \dp\myboxA=\mydepth
   \setbox\myboxB=\vbox
      {\hsize=8cm \rightaligned{{\switchtobodyfont[36pt]#1}}\par
       \startalignment[left,broad] #2\stopalignment}%
   \myheight=\ht\myboxB
   \mydepth=\dp\myboxB
   \ht\myboxB=0pt
   \advance\mydepth by \myheight
   \dp\myboxB=\mydepth
   \box\myboxA\hfill\box\myboxB}

\def\myhead#1#2%
  {\doifemptyelse{#1}{\SimpleHead{#2}}{\ContentsHead{#1}{#2}}}

\setuphead
  [chapter]
  [header=empty,
   style=\bsd,
   command=\myhead,
   page=right,
   after={\blank[2*big]}]
-------------------------------

But is there a better way? This took me surprisingly long and I had to
use the visual debugger to get a clue what was going on. With the
height of both boxes to 0 I've more or less alignment them I think.

(I attempt to emulate the O'Reilly format)

Groetjes,

Berend. (-: