Re: [Groff] Re: begin page blues

[Werner LEMBERG]

> There are certainly cases where one needs to call one or more of the
> pre-processors in the "troff" phase of the pipeline, and even
> interpose a "pre-post-processor between the ditroff output of troff
> and the final post-processor.

For the latter case there is the `.output' request which inserts
arbitrary data into troff's intermediate output file.

> It is certainly possible to [...] write out lines to a temporary
> file or files, use the ".sy" request to run 'tbl' or 'pic' or 'eqn'
> on these saving the results to other temporary files, and then using
> ".so" to read these results back in.

Both TeX and MetaFont use a similar approach, and inspite of the known
limitations it seems to be fairly standard.  Remember that for certain
operation like a generic table of contents or reference support you
need two passes anyway.


    Werner