\Header{deparse}{Expression Deparsing}
\keyword{programming}{deparse}
\keyword{manip}{deparse}
\keyword{data}{deparse}
\begin{Usage}
\begin{verbatim}deparse(expr, width.cutoff = 60)\end{verbatim}
\end{Usage}
\begin{Arguments}
\begin{ldescription}
\item[\texttt{expr}] any \R\ expression in a wider sense than \texttt{\Link{expression}}'s
proper.
\item[\texttt{width.cutoff}] integer in [20,500] determining the cutoff at which
linebreaking is tried.
\end{ldescription}
\end{Arguments}
\begin{Value}
This function turns unevaluated expressions into
character strings (a kind of inverse \texttt{\Link{parse}}).
A typical use of this is to create informative
labels for data sets and plots.  The following example shows a
simple use of this facility.  It uses the functions \texttt{deparse}
and \texttt{substitute} to create labels for a plot which are character
string versions of the actual arguments to the function \texttt{myplot}.\end{Value}
\begin{SeeAlso}
\texttt{\Link{substitute}}, \texttt{\Link{parse}}, \texttt{\Link{expression}}.\end{SeeAlso}
\begin{Examples}
\begin{ExampleCode}
deparse(args(lm))
deparse(args(lm), width = 100)
myplot <-
function(x, y)
    plot(x, y, xlab=deparse(substitute(x)),
        ylab=deparse(substitute(y)))
\end{ExampleCode}
\end{Examples}

