Document Classes ⇒ Warning when "showexpl" used in conjuction with "hyperref"

[fractal.generator]

Dear all,

I used showexpl package in junction with hyperref package.

When I use two consecutive \LTXinputExample commands with captions, I get many warning as follows

! pdfTeX warning (ext4): destination with the same
identifier (name{page.1}) has been already used,
duplicate ignored

Here is my trivial minimal input file:

Code: Select all

 \documentclass{book}

\usepackage{showexpl}
\lstset{explpreset={pos=b}}

\usepackage[a4paper, margin=2cm]{geometry}
\usepackage{hyperref}

\begin{document}

\LTXinputExample[caption={data1}]{data1.tex}
\LTXinputExample[caption={data2}]{data2.tex}

\end{document}

The content of data1.tex :

Code: Select all

111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111 
111111111

The content of data2.tex :

Code: Select all

222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222 
222222222

The warning appears when there are at least two consecutive \LTXinputExample commands with captions.

The warning will disappear when I either
remove the caption from \LTXinputExample
or remove the hyperref package from the preamble.

What should I do to remove the warning?


Regards,


Hayashi

[fractal.generator]

I got the source of problem but I have NOT found the solution.

The warning will disappear when all "caption" keys are removed from the \LTXinputExample.

Anybody can figure out this mistery?


Hayashi

[Juanjo]

I've seen your different posts about code inclusion. I think you've missunderstood the use of the showexpl pakage. It is intended to present LaTeX code and, at the same time, the corresponding output. For C# code, you should directly use listings. I presume that you like the layout provided by showexpl. To obtain it, you can simply copy the contents of showexpl.cfg and adapt it. I've done that. Look at the following example:

Code: Select all

\begin{filecontents*}{program.cs}
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication1
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");
        }
    }
}
\end{filecontents*}

\documentclass{book}

\usepackage[a4paper, margin=2cm]{geometry}
\usepackage{listings}
\usepackage{xcolor}

% --- Taken from showexpl.cfg and slightly modified ---
\definecolor{hellgelb}{rgb}{1,1,0.85}
\definecolor{colKeys}{rgb}{0,0,1}
\definecolor{colIdentifier}{rgb}{0,0,0}
\definecolor{colComments}{rgb}{1,0,0}
\definecolor{colString}{rgb}{0,0.5,0}

\lstset{%
     language=[Sharp]C,%
     float=hbp,%
     basicstyle=\footnotesize\ttfamily,%
     identifierstyle=\color{colIdentifier},%
     keywordstyle=\color{colKeys},%
     stringstyle=\color{colString},%
     commentstyle=\itshape\color{colComments},%
     columns=fixed,
     tabsize=4,%
     frame=single,%
     framerule=1pt,
     extendedchars=true,%
     showspaces=false,%
     showstringspaces=false,%
     numbers=left,%
     numberstyle=\tiny\ttfamily,%
     numbersep=1em,%
     breaklines=true,%
     breakindent=10pt,%
     backgroundcolor=\color{hellgelb},%
     breakautoindent=true,%
     captionpos=t,%
     xleftmargin=1em,%
     xrightmargin=\fboxsep,%
     numbersep=1em%
}
% ------------------------------------------------

\usepackage{hyperref}

\begin{document}
\lstinputlisting[caption={First example}]{program.cs}
\lstinputlisting[caption={Second example}]{program.cs}
\end{document}

The above code compiles perfectly in my computer, without the annoying hyperref warnings you have reported. The filecontents environment just write the file program.cs you gave before editing your posts. Once generated the file (after one LaTeX run), you can remove that environment.

[fractal.generator]

Dear Mr. Juanjo,

thanks for replying.

Even I used showexpl to present TeX or LaTeX (instead of C#) codes and the formatted text, I still got the same errors.

Please see again the first post in this topic, I had made several modification for the sake of illustration showing caption and hyperref are the cause of the warnings. It is just my prediction.

Anyway, thanks for your explanation above. From yours I know more about listings package. It is useful information.




regards,

hayashi

[Juanjo]

It seems that adding the following line to the preamble, after loading hyperref and showexpl, solves the problem:

Code: Select all

\AtBeginDocument{\renewcommand{\theHlstnumber}{\thelstlisting.\arabic{lstnumber}}}

lstnumber is the counter for numbering listing lines, lstlisting numbers listings, and Hlstnumber is the hyperref internal "clone" of lstnumber, used to generate links. Don't ask why this works. There are things in the kernel of hyperref and showexpl that I don't really understand.

[fractal.generator]

Dear Mr. Juanjo,

Your code works successfully

Thank you very much.

If I use \LTXexample, \LTXinputExample, \lstinputlisting, and \lstlistings, should I use \usepackage{listings} in conjuction with \usepackage{showexpl}? Or It is enough to use \usepackage{showexpl} ONLY?

regards,

Hayashi

[Juanjo]

If I use \LTXexample, \LTXinputExample, \lstinputlisting, and \lstlistings, should I use \usepackage{listings} in conjuction with \usepackage{showexpl}? Or It is enough to use \usepackage{showexpl} ONLY?

showexpl already loads listings, so it is useless to try to load it again. In fact, LaTeX has a mechanism to read packages only once.

[fractal.generator]

Thank you very much Mr. Juanjo.

regards,

Hayashi