Can I draw a small arrow from a word to a space-gap on the same line?

Question

I want to illustrate that the const in the following line can also be moved one word to the right. Maybe I can underline the const and draw a slim arced arrow pointing to the next gap?

const int * val
-----___-^

The TeX source is this:

\begin{auflistung} % itemize
  \itm{} % item
  \mono{\fett{const int} * val}
%...
\end{auflistung}

where auflistung serves as an itemize environment, itm as an item, mono as typewriter-tpye, and fett as bold.

Answer 1

This can easily be done using pst-node - the node connection extension of pstricks. Here are a couple of examples:

\documentclass{article}
\usepackage{pst-node}% http://ctan.org/pkg/pst-node
\begin{document}
\begin{itemize}
  \item \texttt{\textbf{\rnode{A}{const} int}\rnode{B}{\strut\ }* val}
    \ncbar[nodesep=2pt,linewidth=0.5pt,angle=90]{->}{A}{B}

  \item \texttt{\textbf{\rnode{C}{const} int}\rnode{D}{\phantom{c}}* val}
    \nccurve[nodesep=2pt,linewidth=0.5pt,angleA=60,angleB=120]{->}{C}{D}

  \item \texttt{\textbf{\rnode{E}{const} int}\rlap{\rnode{F}{\phantom{oo}}} * val}
    \ncarc[nodesep=2pt,linewidth=0.5pt,arcangle=45]{->}{E}{F}

  \item \texttt{\textbf{\rnode{G}{const} int}\rnode{H}{\phantom{t}}* val}
    \ncdiag[nodesep=2pt,linewidth=0.5pt,arm=.3,linearc=.2,angle=90]{->}{G}{H}

\end{itemize}
\end{document}

Your compilation sequence is either latex -> dvips (-> ps2pdf) or xelatex. Modifications to the above code could include arrows/arcs spanning below the code (rather than above), colour, line style and width changes and many more. Read the pst-node documentation or the pstricks documentation (Chapter VII Nodes and Node Connections) for more information.

Answer 2

You could use TikZ for this.

Somewhere at the start of the document, issue

\tikzset{
    every picture/.style={
        remember picture,   % Make nodes available to all TikZ pictures
        inner xsep=0pt, % Remove horizontal padding
        inner ysep=1pt, % Set small vertical padding
        baseline,       % Align TikZ pictures at the baseline
        every node/.style={
            anchor=base % Align all nodes at the baseline
        }
    }
}

Then you can replace the word const with \tikz \node (a) {const}; and the space between int and * with \tikz \node (b) {\hphantom{ }};, creating two nodes (a) and (b) that can then be linked using \tikz [overlay] \draw [red,->] (a.south) to [bend right=70] (b.south);, yielding

Here's the complete document:

\documentclass{article}
\usepackage{tikz}

\begin{document}

\tikzset{
    every picture/.style={
        remember picture,   % Make nodes available to all TikZ pictures
        inner xsep=0pt, % Remove horizontal padding
        inner ysep=1pt, % Set small vertical padding
        baseline,       % Align TikZ pictures at the baseline
        every node/.style={
            anchor=base % Align all nodes at the baseline
        }
    }
}


\begin{itemize} % itemize
  \item{} % item
  \texttt{\tikz \node [anchor=base]  (a) {const}; int\tikz \node  (b) {\hphantom{ }};* val}
    \tikz [overlay] \draw [red,->]  (a.south) to [bend right=70]  (b.south);
\end{itemize}

\end{document}