TRALICS step by step

This file is a primer for Tralics, a LaTeX to XML translator. We explain how to use it. First, we consider a trivial example, that contains only text, then the same one, with latex markup. After that, we give a small example with a configuration file and a last one with another configuration file. We also explain near the end the meaning of all those numbers printed by Tralics at the end of the job. Finally we give a complete non trivial document.

Introduction

This document was written in 2006 for Tralics version 2.9; since then the syntax changed a bit. The following demonstrates some features

If you say tralics hello, the effect is to convert hello.tex into hello.xml. The program takes some arguments; in the example above, there are three arguments separated by spaces. An argument that start with a dash is an option, these are described in options of the tralics command. Some options (like -verbose) take no argument; some take two arguments, and some take a single argument. The following forms are equivalent: -o Hello (a space), -o=Hello (no space, but an equals sign), or -o = Hello (an equals sign, two spaces). You can also say "-o= Hello" (an equal sign optional spaces), provided that the shell removes the doubles quotes and presents this to Tralics as a single string.

All options start with a dash, and all arguments that are not options are input files; unless the -interactivemath option is used, exactly one input file must be given. If you want to convert a file whose name starts with a dash, you must use the -inputfile option. The extension .tex is added to the input file name when missing. You can change the name of the output file into result.xml via the -o result option. Note also that if the input file is foo.xml Tralics will not attempt to convert foo.xml.tex into foo.xml.xml; it makes the assumption that you want foo.xml from foo.tex. This explains the previous error message.

The first document

Assume that the file is called hello.tex and you call Tralics on it. You can say tralics hello -noconfig or tralics -noconfig hello.tex to compile it, the result will be the same. If you just say tralics hello, the default configuration file is loaded, but the resulting XML file is the same.

Let's try to understand all these lines. Lines 1 to 3 identify the software and its release number (here 2.15.4) and the name of the computer. You may have a different version, that produces a different output. In particular, the third line of the XML result is a comment line that holds the version number, and since version 2.9, the compilation date. Thus, the size of XML output can depend on the version.

Line 4 indicates what Tralics will do (before version 2.13, there was an option telling Tralics to check the file for the Raweb, or call LaTeX). Default is to translate the source file in to XML. Lines 5 and 6 say that some configuration file has been read. If the option -noconfig is given, you see No configuration file instead. For details about configuration files, see Configuration files of Tralics .

Everything starting at line 7 is printed after translation is complete. Lines 7 to 16 will be explained in detail later. In earlier versions, you could see on line 8: Seen 0 bibliographic entries (this follows logically from line7); on line 15 Modules with 0, without 0, sections with 0, without 0 (Modules were once used for the raweb), and on line 16 There was no image (however, if images were used, then Tralics says so). Line 11 says that 2398 multiletter control sequences were in use, and 177 macros were created; line 13 says that 1120 elements are constructed at bootstrap time (for instance, \empty and \alpha both occupy a slot in the hash table, one is a macro, and the other is associated to an XML element).

The last three lines indicate that Tralics was happy (no errors found) and generated an XML file. If you call Tralics with option -silent, you will see only the first four lines, and the last three ones. We can look at the result:

Tralics has generated another file, named hello.log. In this case, the content is more or less the same as what is printed on the terminal. As a general rule, everything printed on the terminal is also printed on the transcript file. In what follows we have marked with -- the lines that differs (the banner line This is tralics... is printed in the terminal before options are parsed, the transcript file is generated after its name has been found). We have marked with ++ some lines that are not printed on the terminal. Three lines are marked **, they indicate some omitted stuff, namely the statistics (same as above), File info and Bootstrap info, these are 46 lines starting with \countdef, 43 with \dimendef, 16 with \chardef or \mathchardef, and 23 with \skipdef. These lines explain, for instance, that the chapter counter is the counter number 45.

Our second document

The second example looks a bit more like a LaTeX document. The file is called hello1.tex; its content is:

\documentclass{article}
\begin{document}
Hello, world!
\end{document}

The result of the compilation can be found here. Using an older version of Tralics gives:

The difference between the two compilations is the third line (it holds the Tralics version and the compilation date) and the first: the default file encoding is now UTF-8.

The essential difference between hello.xml and hello1.xml is the DTD and the name of the root element. Here it is <std>; this follows from the following assumptions: Tralics finds a configuration file that, like the standard one, with revision 2.24, maps article to std, and there is no article.tcf file in the search path.

If you compile the file with tralics hello1 -noconfig, the result XML file will be independent of any configuration or tcf file. Translation is the same as above. The transcript file starts as follows:

The start of the transcript file is the same as above, except for the file name and the compilation date. Line 11 says that no configuration file is found (in fact, none is searched); line 12 says that no type was found (obviously). In such a case, the type defaults to the current documentclass (this behavior is the same as the standard configuration file). In the case of hello.tex the main file did not have a \documentclass command; here there is one, as shown on line 13. As a consequence Tralics is ready to read the article.tcf (this is the meaning of potential); but this is inhibited by the -noconfig option. So a default type is used (line 15). This type is std, meaning the the root element is named <std> (it would have been <unknown> in the absence of a \documentclass command).

On line 11 and 12, you can see that the configuration file (by default, it is named .tralics_rc) is search in the current directory then in the ../confdir directory, this can be changed via an option. On line 15, you can see that the potential type is, as above, the current document class, thus article, and the configuration file defines only std (with some aliases). On lines 19 and 20 you can see where the article.tcf file is searched; if such a file is found it is interpreted. Lines 20 and 21 show that article is aliases to std which becomes the type. Finally, line 25 says that the DTD is std.

Lines 28 to 157 in the transcript file show register allocation, they are omitted here. You can see a lots of lines starting with ++. They are printed by the I/O manager. Whenever Tralics tries to open a file, it print a line in the transcript file. For instance, you can see where the configuration file is searched. You can also see that the @ character is made a letter while reading some files; and you can see that cur_file_pos is restored (this variable is used by the class/package mechanism). You can see the action at the end of some files (the virtual file contains the documenthook token list).

After the bootstrap phase, Tralics executes the instructions that come from the configuration file, then those of the main file. In the case of a LaTeX document (i.e., if a document class is found, as indicated on line 16), the file hello1.ult is loaded, when present; line 158 show that this file is search only in the current directory.

When the \documentclass command is seen, the class file is loaded. As you can see, Tralics uses article.clt instead of article.cls. Since the standard classes (book, report and article) share some options, the common code is in std.clt. Instead of foo.sty, a file named foo.plt is used for packages. What you can see in the transcript file is: the second argument of \ProvidesClass, which is also printed on the terminal (line 163), and of \ProvidesFile (line 168), the default options (argument of \ExecuteOptions, line 171) and the actual options (optional argument of \documentclass, empty in this example, line 172). Lines 177 to 186, omitted here, are similar to those shown above.

Our third document

## This is an example of a configuration file for tralics
## Copyright 2006 Inria/apics, Jose' Grimm
## $Id: hello.tcf,v 1.1 2006/07/17 09:09:06 grimm Exp $
## tralics ident rc=hello.tcf $Revision: 1.1 $


DocType = Article classes.dtd
DocAttrib =Foo \World
DocAttrib =A \specialyear
DocAttrib =B  \tralics
DocAttrib =C  \today
BeginCommands
  \def\World{world}
  \def\today{\the\year/\the\month/\the\day}
End

The file defines, in order, the doctype to use in the XML file, four attributes to the document element, and two commands \World, and \today. The \tralics pseudo-command produces Tralics version 2.9 (your mileage may vary), and the \specialyear pseudo-command returns the value of the option -year (for more info, see Tralics options and configuration file).

\newcommand\hello{\uppercase {h}ello}
\documentclass{article}
\begin{document}
\hello, \World!
\end{document}

Compile with tralics hello2.tex -config=hello.tcf -oe8. As mentioned above, the -oe8 option tells Tralics to use UTF-8 encoding for the XML file, this now the default, but was not for version 2.13.0. We assume that the hello.tcf file is found (according to these rules). The translation is the following (for some strange reason the day is shown as 21 and 22).

If we use the following invocation tralics hello2 -config=hello -verbose the transcript file contains much more lines. We give here some of them.

What you can see is where Tralics is searching for the configuration file, and what it found, in particular the DTD.

We have shown on lines 686, 697, 702 to 708, the trace of evaluation of TeX command; you can consult this document for explanations. Line 704 shows that the month is an ordinary number, and the \today command has to be rewritten if its expansion is assumed to give 2015/08/23. Line 708 shows that the day is correct.

Lines 664, 666, 671 are formed of a number in square brackets and some text; the number is the current line number and the text is the content of the line to evaluate. On line 664, you see the last line of the bootstrap code, on line 666 the first line of the main file, on line 719 the second line of the main file. This line contains the \documentclass command that may be used to find the type (in this case the type is given in the configuration file). The lines inserted from the configuration file are inserted before this one (671, 675, 679, 690, 712), or at the start, in case where no document class is given. Lines 679 and 690 correspond to the two DocAttrib lines of the configuration file that could not have been evaluated earlier. As you can see on line 712, the hello2.ult file is inserted after the code from the configuration file, and before the document class. Line 721 says that the line following the \documentclass has been read, because this command has an optional argument.

Lines 722 to 1056 correspond to the loading of the class file. Line 1056 says that we are finished with article.clt and we continue with the main file. Recall line 721; the first token is \begin, it is not an opening bracket, thus not the start of an optional argument, hence is executed now. This command reads an argument, the name of the environment, pushes a new stack level, and executes the command associated to the start of the environment, here \document. There is a hack here, see lines 1061 and 1063: the stack is popped. Everything happens outside an environment; however Tralics still pretends that it is inside document. (Normally, at the end of the environment, all commands that were modified are restored; however, at the end of the document, these commands become useless, so there is no need to save and restore). Line 1064 explains that the \AtBeginDocument hook is about to be evaluated. The next line shows some additional code. Line 1069 shows all tokens to be evaluated; in order: the \AtBeginDocument (empty in this example), the redefinitions implies by \@onlypreamble (the \AtBeginDocument) and the line shown above.

We omit the trace of the document hook and line 4 of the main document. What comes now is \end{document}. The effect is first to execute \enddocument (line 1094) and then \endenv (this is an internal command that pops the stack, its effect can be seen on lines 1100, 1103, 1104). However, the stack should be empty, so we artificially push a new element on the stack (line 1093). Since this is the end of the job, all remaining text is ignored (lines 1095 and 1105). Since version 2.15.4, all text after \end{document}, on the same line is also ignored. All tokens gathered by the \AtEndDocument command are inserted in the current input stream in order to be evaluated (there are none in this example). Line 1096 shows what remains to be executed. The purpose of the first command is to close all chapters, sections, paragraphs, etc, so that, if an index has be generated, it is not inside a paragraph.

Note: when line 1106 is printed the job is not complete, as Tralics the bibliography is not yet handled. Our example file has no bibliography, so nothing special happens.

Our fourth document

## This is an example of a configuration file for tralics
## Copyright 2006 Inria/apics, Jose' Grimm
## $Id: hello3.tcf,v 2.3 2006/07/24 12:09:34 grimm Exp $
## tralics ident rc=helloconf3!

BeginCommands
  \def\World{world}
End

BeginTitlePage
 \maketitle <Title> "" ""
End

DocType = Article classes.dtd
att_language = "language"
xml_stylesheet = "my_stylesheet.css"
xml_stylesheettype = "text/xsl"

BeginCommands
\newcommand\hello{\uppercase {h}ello}
End

BeginTitlePage
 \abstract <abstract> "No abstract given" 
 \author <author> "No author given"
End

A standard configuration file would consist of a single block BeginCommands ... End and a single block BeginTitlePage ... End, instead of two blocks. Nevertheless, you have the right to split your commands as shown here. This configuration file defines five commands. There is no restriction on \hello and \World, but the \maketitle command can be used only once. Moreover, the \abstract and \author commands have to be used before the \maketitle command, they have a default value.

% -*- latex -*- encoding: utf-8
% tralics configuration file 'hello3'
% The previous line magically defines the commands used in this file
\documentclass{book}
\begin{document}
\author{José Grimm}
\maketitle \normalsize
\hello, \World!
\end{document}

The second line of the document tells Tralics to use hello3.tcf as configuration file rather than the default. Since the document class is book, the main element of the XML output has part='true' in its attribute list. It has also language='english', because the default language is language number 0, namely english and the configuration file provides the attribute name to use (value of att_language). Finally, there is a style sheet declaration.

Line 10 of the transcript of the second document says: Input encoding is 1 (iso-8859-1) for the main file. In fact, Tralics maintains a table of transcriptions, zero is for UTF-8, 1 for iso-8859-1, the file inputenc.plt defines ansinew, applemac, etc. A command of the form \usepackage[latin9]{inputenc} tells Tralics to use the encoding associated to latin9, after the \begin{document}. This means that the current file can have more than one encoding; at any point in the file, you can say\input@encoding=1 in order to switch to latin1. This feature is only available for TeX files: all other files (configuration files, package file, bibliographic files, etc) have a fixed encoding. The default encoding is given by an option (-utf8, -latin1, default is latin1). This can be overwritten, if the document contains a line of the form encoding: utf-8 near its beginning.

Assume that your file contains a line with \show ©A\show éabB\show ó©©©C, this is latin1 encoded, and let's pretend it is UTF8. You will get some error messages, see below. At the end of the run, Tralics shows the number of lines converted, the number of lines that caused trouble, and the number of error. For each wrong line, the transcript file will contain something like \show \251A\show \351abB\show \363\251\251\251C (non-ASCII character are printed in base 8).

Statistics

The Tralics distribution contains a lot of test files, some of them should compile without error, o

 1 This is tralics 2.13.0, a LaTeX to XML translator, running on medee
 2 Copyright INRIA/MIAOU/APICS 2002-2008, Jos\'e Grimm

 3 Licensed under the CeCILL Free Software Licensing Agreement
 4 Starting translation of file torture.tex.
 5 Configuration file identification: standard $ Revision: 2.24 $
 6 Read configuration file /user/grimm/home/cvs/tralics/confdir/.tralics_rc.
 7 Configuration file identification: torture.tcf $ Revision: 1.5 $
 8 Read tcf file for type: ../confdir/torture.tcf
 9 Document class: article 2006/08/19 v1.0 article document class for Tralics
10 File `taux2.tex' already exists on the system.
11 Not generating it from this source
12 Translating section command div0: W.
13 \show: 0
14 Translating section command div0: A.
15 Translating section command div0: B.
15 Translating section command div0: C.
17 Translating section command div0: A.
18 Translating section command div0: B.
19 Translating section command div0: C.
20 Warning: junk in table
21 detected on line 3613 of file torture.tex.
22 END OF FILE
23 Bib stats: seen 5(2) entries
24 Seen 3 bibliographic entries
25 Math stats: formulas 751, kernels 167, trivial 5, \mbox 19, large 1, small 59.
?? List stats: short 0, inc 33, alloc 90238.
27 Buffer realloc 28, string 12981, size 247367, merge 232
28 Macros created 1986, deleted 1463; hash size 3062; foonotes 5.
29 Save stack +5189 -5189.
30 Attribute list search 6965(1484) found 2667 in 6419 elements (1117 at boot).
31 Number of ref 31, of used labels 23, of defined labels 31, of ext. ref. 25.
?? Modules with 0, without 0, sections with 2, without 29
33 Input conversion: 49 lines converted.
34 There were 9 images.
35 Following images not defined: x, y, Logo-INRIA-couleur, ../../a_b:c, x_, figure1a, figure1b, figure1c.
36 Output written on torture.xml (164989 bytes).
37 No error found.
38 (For more information, see transcript file torture.log)

Line 4, 5 and 6 show that the standard configuration file has been read, lines 7 and 8 that torture.tcf has been included because of the aliasing mechanism of the standard configuration file.

Line 12, and 14 to 29 show progress: each time a toplevel section is translated, its name is printed.

Line 22 is a result of \typeout command, placed at the end of the document: It tests that every line until the last one have been read.

A complete example

We give here an example of a full document. This uses the RR package, that defines the commands \RRetitle, \RRauthor \RRabstract (this make a non-trivial title page), the fancyvrb package (there is a `pre=pre' somewhere in the text, the associated action is in the package) and natbib, for the citations.

The document was translated using the following invocation: tralics txtc -noentnames -nostraightquotes -nozerowidthspace -trivialmath. We then converted the XML in HTML, it is given here.

The file has been slightly modified: the first line is the correct invocation to tell emacs and Tralics that it is latin1 encoded. The URLs shown here are the ones to use. Starting with version 2.10.7, the line marked COMPATIBILITY PROBLEM finishes the verbatim environment; the one that follows has to be used.

\documentclass{article}   % -*- coding: iso-8859-1 -*-
\usepackage{fancyvrb}
\usepackage{natbib}
\usepackage{RR}

\RRetitle{A sample file for Tralics}
\RRauthor{José Grimm}
\RRabstract{This document shows some commands of \textit{Tralics}.
We use it also to show that characters are converted into the right encoding
in a lot of situations, including commands, titles, indices etc.
The \textit{XML} result is translated via \textsl{XSLT} into \textbf{HTML} 
and available  on the web
\url{http://www-sop.inria.fr/marelle/tralics/txtc.html}.
Source document can be found at
\url{http://www-sop.inria.fr/marelle/tralics/doc-step.html}.} 

\keyword{Latex, XML, HTML, UTF8, Hàn}
\begin{document}


% This is à còmment

\tableofcontents
\section{Who is Hàn}
If you call tralics with options -te1a ou -te8a, the terminal should show 
\verb=^^e0=\index{verb}\footnote{Index here} for the section title; 
if you say -te1, there is a single byte, if you say
-te8, there are two bytes. If you say -e1a or -e8a, the XML file should
contain \verb=&#E0;=, in the case -oe1 ou -oe8, the XML file contains the
characters shown on the terminal.

\def\gobble#1{} %% Used later


The following lines try to demonstrate that Tralics handles 16bit characters.
An error will be signaled because the argument is out of range; but the
character with hex value 312 should be valid; the command defined here
by csname has two characters in its name, it must be followed by an
exclamation point (a space is allowed between the command an the exclamation
point).
\expandafter\def\csname féé\endcsname!{123}
\expandafter\def\csname f^^^^0123\endcsname!{312}
\catcode`\é 11 \catcode"123=11 \catcode65536=11
\féé !! \f^^e9^^^^00e9 !! \f^^^^0123 !!

This is standard verbatim: \verb+a _bç+, \verb*=a _bç=, \verbèa _bçè,
\verb-\verb+ { } $$-, \verb +x+ . Think about this last example.
We index here a word\index{vérb}. Location is just before period.
This is a verbatim environment
\begin{verbatim}
{\let\rm\bf \bf totoé}
<!--this is a comment -->
&Dollar; not &Equals; &Euro;
  \end{verbatim}
% See comment below
\begin{rawxml}
{\let\rm\bf \bf totoé}
<!--this is a comment -->
&Dollar; not &Equals; &Euro;
\end{rawxml}

Note. A verbatim environment neutralises meaning of some commands.
The last line of the verbatim environment should start with an ampersand 
character; since this is a special character in XML, it is represented as
\verb=&amp;= or \verb=&#x26;=. Lines can be numbered; spaces can be replaced
by non-breaking ones; lines can use special fonts; paragraphs can be
no-indented, etc.\index{verb@verb}% same as \index{verb}

On the other hand, a rawxml environment is left unchanged. Remember however
that end-of-line characters and spaces are removed from the end of the line; a
new line character is added at the end of the line. If you remove the comment
between the two environments, replacing it by an empty line, then the second 
environment will be in vertical mode. Otherwise, the end of the verbatim
environment inserts a \verb=\noindent=, and the environment that follows is in
horizontal mode. As a consequence, there will be a P element on the first
line of the raw xml; moreover, since the final space in a paragraph is
removed, you will find the end-P element at the end of the line.%
\index{vérb@verb}% this a new index entry

The translation of the environment contains e-acute (its representation
depends on the output encoding), three ampersand characters, a less than sign,
a greater than sign. The second line is a valid XML comment, the third line is
well-formed XML (it contains three entities, so that the XML is valid only if
the DTD defines these entities); it is very easy to produce invalid and
ill-formed XML.\index{vérb@vérb}% this one alreedy seen

The xmllatex command is to be used with care. It can produce
\xmllatex{Hàn Th&\#x1ebf; Thành}{unused}\footnote{Hàn is the author of
pdftex}. The second argument is meant to be translated by \LaTeX, it is
ignored by Tralics. Instead of \verb=\xmllatex{foo}{bar}=, define a command,
use it in the text, and overwrite it in a ult file (user configuratin file).%
\index{vérb@vérb|bf}% Note that encap is ignored

In the current version, you can say \'{\^e} because the double-accent 
mechanism is implemented, or ^^^^1ebf, this is a character, as valid as the
other ones. This is possible and dangerous too \xmllatex{<TeX/>}{tex}.%
\index{vérb!vèrb} %subitem in index

A verbatim test. We put some stuff in English and French before, in order
to show how it is translated differently. The end of the environment can
contain spaces (see example above), but nothing else.
\language=0
test ligatures: <<>>``''-- et --- !
\language=1
test ligatures: <<>>``''-- et --- !
\numberedverbatim
\begin{verbatim}
test : !@#$%^&*()_$
test : {\foo\} et zxcvbnm,./
\end{verbatim}
\begin{verbatim}
test ZXVBNM<>? ~
test \verb+\verb-xx-+
test ligatures: <<>>``''-- et --- !
 \end{verbatim} Not this one COMPATIBILITY PROBLEM
 \end+{verbatim} Not this one %% + added in version 2.11 WORKS
\end{notverbatim}
\end{verbatim}

\gobble{
\end{verbatim}
}

\unnumberedverbatim
Verbatim without line numbers. 
\begin{verbatim}
test : !@#$%^&*()_$
test : {\foo\} et zxcvbnm,./
test ZXVBNM<>? ~
test \verb+\verb-xx-+
test ligatures: <<>>``''-- et --- !
test BL : \\738! et \\838!.
\end{verbatim}
The BL test is funny; why should it fail? a long long time ago, before
it was called Tralics, our translator was written in Perl, and such a line 
was illegal; the math was converted by Omega, see \cite{place99}. We cite also
\citeyear{mKay}, and \citefullauthor{mathml2}.

We now test the verbatim extensions. We start with Verbatim
and demonstrate the counting possibilities
\begin{Verbatim}                   [numbers=true]
test line 1a
test line 1b
\end{Verbatim}
and without numbers
\begin{Verbatim}
[numbers=true]test line 2a
[numbers=true]test line 2b
\end{Verbatim}
\begin{Verbatim} %
[numbers=true] this text is ignored
The environment has an optional argument; spaces but no newlines are allowed
between brace and bracket; what follows the argument on the line is ignored
\end{Verbatim}

We put here the first character of the line in italics
\def\verbatimfont#1{{\it #1}}
\def\verbatimnumberfont{\large}
\count3=4
\begin{Verbatim}[counter=3]
5 we use here counter number 3
6 for counting lines
\end{Verbatim}
Define our Verbatim hook now.
\expandafter\def\csname Verbatim@hook\endcsname{pre=pre,style=latex}
\begin{Verbatim}[counter=03]
7 we use here counter number 03 (the same)
8 but the HTML output differs a lot.
\end{Verbatim}
\newcounter{vbcounter}
\setcounter{vbcounter}{\count3}
\begin{Verbatim}[counter=vbcounter]
9 we use here counter named vbcounter
10 initialised to the value of the previous counter
\end{Verbatim}
\begin{Verbatim}[counter=vbcounter]
11 yet another verbatim line (ok with é^^e9?)
\end{Verbatim}

\let\verbatimfont\tt
\def\verbatimnumberfont#1{\xbox{vbnumber}{#1}}

\DefineVerbatimEnvironment{xverbatim}{Verbatim}{pre=pre,style=latex}
\begin{xverbatim}[numbers=left]
note that, if no counter is specified, it is FancyVerbLine
\end{xverbatim}
\begin{xverbatim}[numbers=left,firstnumber=last,style=log]
and that the first line is numbered one by default.
Of course, options given on the line have precedence over options
inherited from the definition.
\end{xverbatim}

\newenvironment{centré}{\centering}{}
\begin{centré}
In French, centré means centered.
\end{centré}

\DefineShortVerb{\|}
\SaveVerb{DU}|$_|\def\DU{\UseVerb{DU}} %$
\section{Short  Verb, as in \DU}
\let\verbatimfont\sffamily
Test of |\DefineShortVerb| and |\UndefineShortVerb|. Normally
the bar is used, but 16bit characters are possible. Example, with itrema:
\DefineShortVerb{\ï}
|toto| ïxï |+x-| ï|t|ï,
\UndefineShortVerb{\ï}
and without:
|toto| ïxï |+x-| ï|t|ï
Spaces: like this |+ +| or that \fvset{showspaces=true}|+ +|
Verbatimfoo: \verb|+ foo +*foo*foo*|.

\def\verbatimfont#1{{#1}}
\def\verbprefix#1{A#1A}
\def\verbatimprefix#1{B#1B}

\SaveVerb{Ç}|}|\def\FE{\UseVerb{Ç}}
\DefineShortVerb{\+}
\SaveVerb{VE}+|+\def\VE{\UseVerb{VE}}
\UndefineShortVerb{\+}
\UndefineShortVerb{\|}

Test of useverb \UseVerb{Ç}, \FE,\VE, \DU.
\begin{verbatim}
We have changed the font, and added a prefix
Spaces are special
\end{verbatim}

Switch to English, for colons in URLs \language=0

\bibliography{tralics}

\end{document}

Getting started with Tralics