Wolfgang,

I did define the various variants in order to parametrize vtop, vbox and vcenter through parameters top, bottom, center.
 
Happily there proved to be a remedy: place everything inside an \hbox and the error goes away. Without problematic whitespace or other nasty side effects, it seems.  But, although the panic is over now :-), I am still curious to know why it worked before and raises an error now.

as for the definition of \placexlocation, it comes from:
\def\setupplacex{\getparameters[placex]}
\setupplacex[% default parameters
...
location=center,%
...
]%
and I checked that it had the value: center.

But if you are interested, I can send you the module code.

dr. Hans van der Meer


On 7 Jun 2020, at 12:20, Wolfgang Schuster <wolfgang.schuster.lists@gmail.com> wrote:

Hans van der Meer schrieb am 07.06.2020 um 12:07:
A problem has arisen up since previous versions, where code without a problem now raises an error.
This is the afflicted code:
% Assign values to \locationbox.
\doif{top}{\placexlocation}%
{\def\startlocationbox{\vtop\bgroup\vss}}%
\doif{center}{\placexlocation}%
{\def\startlocationbox{\vcenter\bgroup}}%
\doif{bottom}{\placexlocation}%
{\def\startlocationbox{\vbox\bgroup}}%
And it is used here:
\setbox\placexbox=\startlocationbox
\ignorespaces
Previously this worked without a hitch, now the error is:
tex error       > tex error on line 9 in file ./familie-events.tex: ! A <box> was supposed to be here
<to be read again>
\vcenter
\startlocationbox ->\vcenter
                             \bgroup
\dostartcontentplacexinline ...ables \par \setbox \placexbox =\startlocationbox
                                                                                 \ignorespaces
<to be read again> \syst_helpers_single_empty_one_nop
                                   \xmlflush
\21>:xmlplc:placexcontent ...le=\xmlatt {#1}{alttitle}]}\startcontent \xmlflush
                                                                                 {#1}\stopcontent
l.9 }
I can try to make a minimal example, but not without the afflicted module of some 800 lines. So perhaps the problem will be located by the experts at first sight. It is of course the \vcenter playing havoc, because replacing it by \vtop or \vbox makes the error disappear.
Thanks for looking into it, because my work more or less depends on this code working in good order.

How so you define \placexlocation?

Wolfgang
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