Error compiling a document with realscripts

[georgd]

Recently, realscripts produces some errors of undefined control sequences and extra }’s. It’s an up-to-date TL2012 with additionally xetex from tlcontrib.

MWE:

\documentclass{minimal}
\usepackage{fontspec}
\usepackage{realscripts}
\begin{document}
\textsubsuperscript{235}{92}U
\end{document}

log:

This is XeTeX, Version 3.1415926-2.5-0.9999.0 (TeX Live 2013/dev) (format=xelatex 2013.3.15)  17 MAR 2013 14:54
entering extended mode
 restricted \write18 enabled.
 %&-line parsing enabled.
**subsuper.tex
(./subsuper.tex
LaTeX2e <2011/06/27>
Babel  and hyphenation patterns for english, dumylang, nohyphenation, ge
rman-x-2012-05-30, ngerman-x-2012-05-30, afrikaans, ancientgreek, ibycus, arabi
c, armenian, basque, bulgarian, catalan, pinyin, coptic, croatian, czech, danis
h, dutch, ukenglish, usenglishmax, esperanto, estonian, ethiopic, farsi, finnis
h, french, friulan, galician, german, ngerman, swissgerman, monogreek, greek, h
ungarian, icelandic, assamese, bengali, gujarati, hindi, kannada, malayalam, ma
rathi, oriya, panjabi, tamil, telugu, indonesian, interlingua, irish, italian, 
kurmanji, latin, latvian, lithuanian, mongolian, mongolianlmc, bokmal, nynorsk,
 piedmontese, polish, portuguese, romanian, romansh, russian, sanskrit, serbian
, serbianc, slovak, slovenian, spanish, swedish, turkish, turkmen, ukrainian, u
ppersorbian, welsh, loaded.
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.

(/usr/local/texlive/2012/texmf-dist/tex/latex/euenc/eu1lmss.fd
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. 108.
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\l_fontspec_tmp_int=\count114
LaTeX Info: Redefining \itshape on input line 2091.
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(/usr/local/texlive/2012/texmf-dist/tex/latex/fontspec/fontspec.cfg)))
(/usr/local/texlive/2012/texmf-dist/tex/latex/realscripts/realscripts.sty
Package: realscripts 2013/02/27 v0.3b Access OpenType subscripts and superscrip
ts
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\subsupersep=\dimen138
) (./subsuper.aux)
\openout1 = `subsuper.aux'.

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LaTeX Font Info:    Encoding `OT1' has changed to `EU1' for symbol font
(Font)              `operators' in the math version `normal' on input line 4.
LaTeX Font Info:    Overwriting symbol font `operators' in version `normal'
(Font)                  OT1/cmr/m/n --> EU1/lmr/m/n on input line 4.
LaTeX Font Info:    Encoding `OT1' has changed to `EU1' for symbol font
(Font)              `operators' in the math version `bold' on input line 4.
LaTeX Font Info:    Overwriting symbol font `operators' in version `bold'
(Font)                  OT1/cmr/bx/n --> EU1/lmr/m/n on input line 4.
LaTeX Font Info:    Overwriting symbol font `operators' in version `normal'
(Font)                  EU1/lmr/m/n --> EU1/lmr/m/n on input line 4.
LaTeX Font Info:    Overwriting math alphabet `\mathrm' in version `normal'
(Font)                  EU1/lmr/m/n --> EU1/lmr/m/n on input line 4.
LaTeX Font Info:    Overwriting math alphabet `\mathit' in version `normal'
(Font)                  OT1/cmr/m/it --> EU1/lmr/m/it on input line 4.
LaTeX Font Info:    Overwriting math alphabet `\mathbf' in version `normal'
(Font)                  OT1/cmr/bx/n --> EU1/lmr/bx/n on input line 4.
LaTeX Font Info:    Overwriting math alphabet `\mathsf' in version `normal'
(Font)                  OT1/cmss/m/n --> EU1/lmss/m/n on input line 4.
LaTeX Font Info:    Overwriting math alphabet `\mathtt' in version `normal'
(Font)                  OT1/cmtt/m/n --> EU1/lmtt/m/n on input line 4.
LaTeX Font Info:    Overwriting symbol font `operators' in version `bold'
(Font)                  EU1/lmr/m/n --> EU1/lmr/bx/n on input line 4.
LaTeX Font Info:    Overwriting math alphabet `\mathrm' in version `bold'
(Font)                  EU1/lmr/m/n --> EU1/lmr/bx/n on input line 4.
LaTeX Font Info:    Overwriting math alphabet `\mathit' in version `bold'
(Font)                  OT1/cmr/bx/it --> EU1/lmr/bx/it on input line 4.
LaTeX Font Info:    Overwriting math alphabet `\mathsf' in version `bold'
(Font)                  OT1/cmss/bx/n --> EU1/lmss/bx/n on input line 4.
LaTeX Font Info:    Overwriting math alphabet `\mathtt' in version `bold'
(Font)                  OT1/cmtt/m/n --> EU1/lmtt/bx/n on input line 4.
LaTeX Font Info:    External font `cmex10' loaded for size
(Font)              <7> on input line 5.
LaTeX Font Info:    External font `cmex10' loaded for size
(Font)              <5> on input line 5.
! Undefined control sequence.
\textsubsuperscript code ...x }}\prg_case_str:nnn 
                                                  {#2}{{l}{\use_i:nnn }{c}{\...
l.5 \textsubsuperscript{235}{92}
                                U
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.

! Argument of \use_i:nnn has an extra }.
 
                \par 
l.5 \textsubsuperscript{235}{92}
                                U
I've run across a `}' that doesn't seem to match anything.
For example, `\def\a#1{...}' and `\a}' would produce
this error. If you simply proceed now, the `\par' that
I've just inserted will cause me to report a runaway
argument that might be the root of the problem. But if
your `}' was spurious, just type `2' and it will go away.

Runaway argument?
! Paragraph ended before \use_i:nnn was complete.
 
                   \par 
l.5 \textsubsuperscript{235}{92}
                                U
I suspect you've forgotten a `}', causing me to apply this
control sequence to too much text. How can we recover?
My plan is to forget the whole thing and hope for the best.

! Argument of \use_ii:nnn has an extra }.
 
                \par 
l.5 \textsubsuperscript{235}{92}
                                U
I've run across a `}' that doesn't seem to match anything.
For example, `\def\a#1{...}' and `\a}' would produce
this error. If you simply proceed now, the `\par' that
I've just inserted will cause me to report a runaway
argument that might be the root of the problem. But if
your `}' was spurious, just type `2' and it will go away.

Runaway argument?
! Paragraph ended before \use_ii:nnn was complete.
 
                   \par 
l.5 \textsubsuperscript{235}{92}
                                U
I suspect you've forgotten a `}', causing me to apply this
control sequence to too much text. How can we recover?
My plan is to forget the whole thing and hope for the best.

! Argument of \use_iii:nnn has an extra }.
 
                \par 
l.5 \textsubsuperscript{235}{92}
                                U
I've run across a `}' that doesn't seem to match anything.
For example, `\def\a#1{...}' and `\a}' would produce
this error. If you simply proceed now, the `\par' that
I've just inserted will cause me to report a runaway
argument that might be the root of the problem. But if
your `}' was spurious, just type `2' and it will go away.

Runaway argument?
! Paragraph ended before \use_iii:nnn was complete.
 
                   \par 
l.5 \textsubsuperscript{235}{92}
                                U
I suspect you've forgotten a `}', causing me to apply this
control sequence to too much text. How can we recover?
My plan is to forget the whole thing and hope for the best.

Package realscripts Warning: Unknown alignment option `l'.
(realscripts)                One of `l', `c', `r', only on input line 5.

! Argument of \use_i:nnn has an extra }.
 
                \par 
l.5 \textsubsuperscript{235}{92}
                                U
I've run across a `}' that doesn't seem to match anything.
For example, `\def\a#1{...}' and `\a}' would produce
this error. If you simply proceed now, the `\par' that
I've just inserted will cause me to report a runaway
argument that might be the root of the problem. But if
your `}' was spurious, just type `2' and it will go away.

Runaway argument?
! Paragraph ended before \use_i:nnn was complete.
 
                   \par 
l.5 \textsubsuperscript{235}{92}
                                U
I suspect you've forgotten a `}', causing me to apply this
control sequence to too much text. How can we recover?
My plan is to forget the whole thing and hope for the best.

[1] (./subsuper.aux) ) 
Here is how much of TeX's memory you used:
 13534 strings out of 493985
 304076 string characters out of 3150273
 288683 words of memory out of 3000000
 16741 multiletter control sequences out of 15000+200000
 3696 words of font info for 21 fonts, out of 3000000 for 9000
 1144 hyphenation exceptions out of 8191
 46i,4n,30p,584b,100s stack positions out of 5000i,500n,10000p,200000b,50000s

Output written on subsuper.pdf (1 page).

[wspr]

Thanks for catching this! I've uploaded a new version to CTAN; should appear shortly. Sorry for the inconvenience.

[georgd]

Thank you!