<ditaa noedgesep>
    +---------+   +-------\    /-------\
    |         |   | ditaa |    |       |
    |  Text   |   +-------+    |diagram|
    |Document |   |!magic!|    |       |
    |     {d} |   |  c978 |    |       |
    +----+----+   \---*---+    \---*---/
         |            ^            ^
         |       Lots |of work     |
         +----------->*----------->*---------+
                                   |         |
                                   v         v
                               +---+---+ +---+---+
                               |  {io} | |  {io} |
                               |       | |       |
                               |       | |       |
                               +-------+ +-------+
</ditaa>