Xypic compiling error with auctex

Question

I have a problem with the following piece of code:

$\xymatrix{ {X_{2}} \ar@<0.6ex>[r]^-{p_{0}} \ar@<-0.6ex>[r]_-{p_{1}} & {X_{1}} }$

is made into a LaTeX macro as:

\newcommand{\arrp}[4]{\mbox{$\xymatrix{ {#3} \ar@<0.6ex>[r]^-{#1}\ar@<-0.6ex>[r]_-{#2} & {#4} }$}}

which is called as

\arrp{p}{q}{A}{B}

Normal \LaTeX compilation works either way. However, for AucTeX, the former when written down in the tex file compiles with no issues. However, whenver it is written in the latter way it complains as follows:

ERROR: Argument of \next@ has an extra }.

--- TeX said --- \par l.186 ...}}}{\comp{e}{\cod{}}}{\Bb{X}_1}{\Bb{X}_1} . Since from equation \eqr... --- HELP --- From the .log file...

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.

I would appreciate your help if you could let me know where I am going wrong.

With my regards and thanks,

partha

Answer 1

Please find the code here:

\documentclass[12pt]{article}

\usepackage{amsbsy, amsmath, amssymb, amsthm, bbold, xcolor, xspace}
\usepackage[all,pdf]{xy}

\usepackage{Documents/tex/essentials/symbols}  % line 1


%\input{Documents/tex/essentials/symbols-command} % line 2

%\newcommand{\arrp}[4]{\mbox{$\xymatrix{ {#3} \ar@<0.6ex>[r]^-{#1} \ar@<-0.6ex>[r]_-{#2} %& {#4}}$}} %line 3


\begin{document}


Using usual Xy-pic:
$\xymatrix{ {A} \ar@<0.6ex>[r]^-{f} \ar@<-0.6ex>[r]_-{g} & {B}}$

Using the {\tt symbols.sty} package which contains all my TeX macros:

\arrp{f}{g}{A}{B}


\end{document}


%%% Local Variables:
%%% mode: latex
%%% TeX-master: t
%%% End:

Let me list my attempts and their outcomes:

• With Line 2 and Line 3 commented out, as it is now, the second parallel pair of arrows does not come, the first comes however. The errors produced is given in the code block:

./testXy.tex:21: Argument of \next@ has an extra }.
<inserted text> 
                \par 
l.21 \arrp{f}{g}{A}{B}
                      
Runaway argument?
h\dir 
./testXy.tex:21: Paragraph ended before \next@ was complete.
<to be read again> 
                   \par 

or

l.21 \arrp{f}{g}{A}{B}
                      
./testXy.tex:21: Extra }, or forgotten $.
\entrybox ...dimen@ \D@p \dp \z@ =\dimen@ \boxz@ }
                                                  
l.21 \arrp{f}{g}{A}{B}
                      
./testXy.tex:21: Extra }, or forgotten $.
<inserted text> \egroup 
                        \def \Drop@@ {\styledboxz@ }\def \Connect@@ {\straig...l.21 \arrp{f}{g}{A}{B}

or

l.21 \arrp{f}{g}{A}{B}
                      
./testXy.tex:21: Extra }, or forgotten $.
\entrybox ...dimen@ \D@p \dp \z@ =\dimen@ \boxz@ }
                                                  
l.21 \arrp{f}{g}{A}{B}
                      
./testXy.tex:21: Extra }, or forgotten $.
<inserted text> \egroup 
                        \def \Drop@@ {\styledboxz@ }\def \Connect@@ {\straig...l.21 \arrp{f}{g}{A}{B}

or like

./testXy.tex:21: Xy-pic error: illegal <dir>: \dir [r]^-{f} not defined.
\xyerror@ ...#2}\fi \errmessage {Xy-pic error: #1}
                                                  }
l.21 \arrp{f}{g}{A}{B}
                      
./testXy.tex:21: A <box> was supposed to be here.
<to be read again> 
                   \toks@ 
l.21 \arrp{f}{g}{A}{B}
                      
./testXy.tex:21: Xy-pic error: illegal <dir>: \dir \ar@ <-0.6ex>[r]_-{g} not defined.
\xyerror@ ...#2}\fi \errmessage {Xy-pic error: #1}
                                                  }

or

61>
./testXy.tex:24: Improper \prevdepth.
\newpage ...everypar {}\fi \par \ifdim \prevdepth 
                                                  >\z@ \vskip -\ifdim \prevd...l.24 \end{document}
                   
./testXy.tex:24: Missing } inserted.
<inserted text> 
                }
./testXy.tex:24: Xy-pic error: An \xy environment is not closed correctly..
\xyerror@ ...#2}\fi \errmessage {Xy-pic error: #1}
                                                  }
l.24 \end{document}

I have put snippets of all forms of errors that have come while the \LaTeX engine was trying to find for the error. Obviously there were repetitions, which I excluded.

• With Line 1 and Line 3 commented out and Line 2 in place, there is no problem and output is produced as expected.

• With Line 1 and Line 2 commented there was also error:

Runaway argument?
{\mbox {$\xymatrix { {##3} \ar @<0.6ex>[r]^-{##1} \ar @<-0.6ex>[r]_-{\ETC.
! File ended while scanning use of \@argdef.
<inserted text> 

and the process aborted! But there is no ##1 or likewise....

Yet, the file symbols.sty is just the file symbols-command.tex made into a style file instead of making an input of .tex file. I was using these symbols for pretty long time using the *symbols-command.tex" file as input and had not problems. The problem started when I made the style file.

The line is question is obviously the construct in Line 3.

Any help would be appreciated.

With my regards and thanks,

partha