[XeTeX] New environment fails in float

[Gareth Hughes]

I'm having problems with an environment definition. Using the xparse and
etoolbox packages, I have created the environment syriacpoem in my .sty
file. It is defined as

%%%%%%
\DeclareDocumentEnvironment{syriacpoem}{so}{%
  \ifbool{xsy at kashpoem}{\begin{syrjust}}{}%
    \begin{syriac}%
      \ifstrequal{#2}{estr}{\estrfont}{}%
      \ifstrequal{#2}{serto}{\sertofont}{}%
      \ifstrequal{#2}{madnha}{\madnhafont}{}%
      \ifstrequal{#2}{east}{\madnhafont}{}%
      \ifstrequal{#2}{estrangelo}{\estrfont}{}%
      \ifstrequal{#2}{estrangela}{\estrfont}{}%
  \IfBooleanTF #1 {\begin{traditionalpoem*}}{\begin{traditionalpoem}}}{%
  \IfBooleanTF #1
{\end{traditionalpoem*}}{\end{traditionalpoem}}\end{syriac}%
  \ifbool{xsy at kashpoem}{\end{syrjust}}{}}
%%%%%%

The boolean xsy at kashpoem is true if word-stretching justification is
required. The environment syrjust provides that justification using a
version of Jonathan Kew and Fr Michael Gilmary's implementation with
interchartoks shown on this list. The syriac environment is from
polyglossia, ensuring RTL and a Syriac font, and it is followed by
optional font switches for other Syriac fonts. Then either the starred
or unstarred version of bidipoem's traditionalpoem environment is turned
on depending on the presence or absence of a star in the document
command. The end of environment closes all these nested environments in
order.

This new environment works as expected in normal tests. However, as I
came to document it, I wanted to give an example in a framed float in my
package documentation. However, the new environment breaks inside the
float. My framed box uses the fancybox package and is defined as

%%%%%%
\newenvironment{example}[1]%
  {\begin{figure}[h]\begin{center}\begin{Sbox}\begin{minipage}{#1}}%
  {\end{minipage}\end{Sbox}\ovalbox{\TheSbox}\end{center}\end{figure}}
%%%%%%

Obviously, something in the environment is upsetting my example box. If
I replace my syriacpoem environment with the nested environments it
calls, it works perfectly. So, there's nothing wrong with what the
environment does, just in how it does it. The lengthy section of the log
dealing with this is below. Can anyone suggest how to fix this?

Thanks,

Gareth.

Log extract follows:

! Missing number, treated as zero.
<to be read again>
                   \group_end:
l.314 ^^I\end{syriacpoem}

A number should have been here; I inserted `0'.
(If you can't figure out why I needed to see a number,
look up `weird error' in the index to The TeXbook.)


! LaTeX Error: \begin{traditionalpoem*} on input line 305 ended by
\end{traditi
onalpoem}.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...

l.314 ^^I\end{syriacpoem}

Your command was ignored.
Type  I <command> <return>  to replace it with another command,
or  <return>  to continue without it.

! Extra }, or forgotten \endgroup.
\endminipage ...pagefalse \color at endgroup \egroup
                                                  \if at RTL \endL \fi
\egroup ...
l.316 ^^I\end{example}

I've deleted a group-closing symbol because it seems to be
spurious, as in `$x}$'. But perhaps the } is legitimate and
you forgot something else, as in `\hbox{$x}'. In such cases
the way to recover is to insert both the forgotten and the
deleted material, e.g., by typing `I$}'.

! Extra }, or forgotten \endgroup.
\endminipage ...\egroup \if at RTL \endL \fi \egroup
                                                  \egroup \expandafter
\@iii...
l.316 ^^I\end{example}

I've deleted a group-closing symbol because it seems to be
spurious, as in `$x}$'. But perhaps the } is legitimate and
you forgot something else, as in `\hbox{$x}'. In such cases
the way to recover is to insert both the forgotten and the
deleted material, e.g., by typing `I$}'.

! Extra }, or forgotten \endgroup.
\endminipage ...\if at RTL \endL \fi \egroup \egroup
                                                  \expandafter
\@iiiparbox \...
l.316 ^^I\end{example}

I've deleted a group-closing symbol because it seems to be
spurious, as in `$x}$'. But perhaps the } is legitimate and
you forgot something else, as in `\hbox{$x}'. In such cases
the way to recover is to insert both the forgotten and the
deleted material, e.g., by typing `I$}'.


! LaTeX Error: Misplaced \endSbox! Should be in LR mode.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...

l.316 ^^I\end{example}

You're in trouble here.  Try typing  <return>  to proceed.
If that doesn't work, type  X <return>  to quit.


! LaTeX Error: \begin{minipage} on input line 304 ended by \end{Sbox}.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...

l.316 ^^I\end{example}

Your command was ignored.
Type  I <command> <return>  to replace it with another command,
or  <return>  to continue without it.

! Missing } inserted.
<inserted text>
                }
l.316 ^^I\end{example}

I've inserted something that you may have forgotten.
(See the <inserted text> above.)
With luck, this will get me unwedged. But if you
really didn't forget anything, try typing `2' now; then
my insertion and my current dilemma will both disappear.

! Missing } inserted.
<inserted text>
                }
l.316 ^^I\end{example}

I've inserted something that you may have forgotten.
(See the <inserted text> above.)
With luck, this will get me unwedged. But if you
really didn't forget anything, try typing `2' now; then
my insertion and my current dilemma will both disappear.


! LaTeX Error: \TheSbox is empty!.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...

l.316 ^^I\end{example}

You're in trouble here.  Try typing  <return>  to proceed.
If that doesn't work, type  X <return>  to quit.


! LaTeX Error: Something's wrong--perhaps a missing \item.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...

l.316 ^^I\end{example}

Try typing  <return>  to proceed.
If that doesn't work, type  X <return>  to quit.


! LaTeX Error: Something's wrong--perhaps a missing \item.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...

l.316 ^^I\end{example}

Try typing  <return>  to proceed.
If that doesn't work, type  X <return>  to quit.


! LaTeX Error: \begin{Sbox} on input line 304 ended by \end{center}.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...

l.316 ^^I\end{example}

Your command was ignored.
Type  I <command> <return>  to replace it with another command,
or  <return>  to continue without it.

! Missing } inserted.
<inserted text>
                }
l.316 ^^I\end{example}

I've inserted something that you may have forgotten.
(See the <inserted text> above.)
With luck, this will get me unwedged. But if you
really didn't forget anything, try typing `2' now; then
my insertion and my current dilemma will both disappear.

! Extra }, or forgotten \endgroup.
\@endfloatbox ...pagefalse \outer at nobreak \egroup
                                                  \color at endbox
l.316 ^^I\end{example}

I've deleted a group-closing symbol because it seems to be
spurious, as in `$x}$'. But perhaps the } is legitimate and
you forgot something else, as in `\hbox{$x}'. In such cases
the way to recover is to insert both the forgotten and the
deleted material, e.g., by typing `I$}'.


! LaTeX Error: \begin{figure} on input line 304 ended by \end{example}.

See the LaTeX manual or LaTeX Companion for explanation.
Type  H <return>  for immediate help.
 ...

l.316 ^^I\end{example}

Your command was ignored.
Type  I <command> <return>  to replace it with another command,
or  <return>  to continue without it.

! Missing } inserted.
<inserted text>
                }
l.316 ^^I\end{example}

I've inserted something that you may have forgotten.
(See the <inserted text> above.)
With luck, this will get me unwedged. But if you
really didn't forget anything, try typing `2' now; then
my insertion and my current dilemma will both disappear.