How to use lstlisting "moredelim" inside quoted text [RESOLVED, but with possible caveats for others]

Question

update: Arun's answer, below, works for me, since I'm not using syntax highlighting anyway. Thanks!

Here's my original question:

I use the following setting to allow me to mark text as bold within an lstlisting environment by putting three asterisks at the beginning and end of the bolded section:

 \lstset{moredelim=[is][\bfseries]{***}{***}}

This works find most of the time, but fails when I try to use it within quoted text. For example, the following works:

 \begin{lstlisting}
 this is a ***test***!
 \end{lstlisting}

but the following doesn't:

 \begin{lstlisting}
 "this is a ***test***!"
 \end{lstlisting}

The second form simply prints literal asterisks. Is there a way to turn off the special behaviour of lstlisting when within quotes?

Bryan

edit: I've added a complete minimal example below.

\documentclass{article}

\usepackage{listings}
\lstset{ % Set options for ``listing'':
language=C++,
commentstyle=,
keywordstyle=,
identifierstyle=,
basicstyle=\ttfamily,
breaklines=false,
frame=,
showstringspaces=false
}
\lstset{moredelim=[is][\bfseries]{***}{***}}

\begin{document}

This works:

 \begin{lstlisting}
 this is a ***test***!
 \end{lstlisting}

This doesn't:

 \begin{lstlisting}
 "this is a ***test***!"
 \end{lstlisting}

\end{document}

Answer 1

A possible solution is to add morestring=*[b]" to your \lstset. This redeclares the "..." string syntax, but the asterisk means that listings still applies its formatting inside of these strings.

Here's my code; since LaTeX doesn't have a bold typewriter font by default, I used italics instead.

\documentclass{article}
\usepackage{listings}
\lstset{ % Set options for ``listing'':
    language=C++,
    % ... same options ... 
    showstringspaces=false,
    morestring=*[b]"
}
\lstset{moredelim=[is][\itshape]{***}{***}}
\begin{document}
\begin{lstlisting}
this is a ***test***!
\end{lstlisting}
With quotes:
\begin{lstlisting}
"this is a ***test***!"
\end{lstlisting}
\end{document}

However, there is a caveat: this redefinition means that listings applies all formatting inside strings, not just your new delimiter. For example, this is a C++ keyword, so if you use \lstset{keywordstyle=\color{blue}}, then this is colored inside quotes as well:

This might not be desired behavior. If so, you'll probably have to use something other than moredelim, such as escapeinside.