>> The problem is that the .tag request confuses the
>> .br request.
I've now analyzed the problem. Sorry for the long delay.
> I do not understand why the output of a tag-unaware device can
> depend on tags. I still think it is a bug or a design problem.
The requests `.tag' and `.taga' insert a node, causing the problems
you experience with `.SP'. From a user's point of view, it behaves
similarly to inserting `\&'.
> I have successfully used input line traps to fix this for my
> particular task (no drawing requests, multicolumn output and
> complicated nested diver- stions), but I couldn't derive a generic
> criteria to determine whether a .tag request has been called so it
> could be handled specially in .SP to stop it from generating excess
> vertical space...
It is not possible to find out the type of the last node in the line
node list. However, if you say
.vpt 0
.DEVTAG-EO-H
.br
.sp -1
.vpt 1
the vertical effect of .DEVTAG-EO-H is cancelled; this works just fine
with your example. Can you try whether this works with your documents
as a patch to to mm also?
Werner
