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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Do not modify this file since it was automatically generated from:
%
% withCapture.R
%
% by the Rdoc compiler part of the R.oo package.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\name{withCapture}
\alias{withCapture}
\alias{evalCapture}
\title{Evaluates an expression and captures the code and/or the output}
\description{
Evaluates an expression and captures the code and/or the output.
}
\usage{
withCapture(expr, replace=getOption("withCapture/substitute", ".x."), code=TRUE,
output=code, ..., max.deparse.length=getOption("max.deparse.length", 10000), trim=TRUE,
newline=getOption("withCapture/newline", TRUE), collapse="\n", envir=parent.frame())
}
\arguments{
\item{expr}{The R expression to be evaluated.}
\item{replace}{An optional named \code{\link[base]{list}} used for substituting
symbols with other strings.}
\item{code}{If \code{\link[base:logical]{TRUE}}, the deparsed code of the expression is echoed.}
\item{output}{If \code{\link[base:logical]{TRUE}}, the output of each evaluated subexpression
is echoed.}
\item{...}{Additional arguments passed to \code{\link[R.utils]{sourceTo}}
which in turn passes arguments to \code{\link[base]{source}}().}
\item{max.deparse.length}{A positive \code{\link[base]{integer}} specifying the maximum
length of a deparsed expression, before truncating it.}
\item{trim}{If \code{\link[base:logical]{TRUE}}, the captured rows are trimmed.}
\item{newline}{If \code{\link[base:logical]{TRUE}} and \code{collapse} is non-\code{\link[base]{NULL}}, a newline
is appended at the end.}
\item{collapse}{A \code{\link[base]{character}} string used for collapsing the captured
rows. If \code{\link[base]{NULL}}, the rows are not collapsed.}
\item{envir}{The \code{\link[base]{environment}} in which the expression is evaluated.}
}
\value{
Returns a \code{\link[base]{character}} string class 'CapturedEvaluation'.
}
\examples{
print(withCapture({
n <- 3
n
for (kk in 1:3) {
printf("Iteration #\%d\n", kk)
}
print(Sys.time())
type <- "horse"
type
}))
## > n <- 3
## > n
## [1] 3
## > for (kk in 1:3) {
## + printf("Iteration #\%d\n", kk)
## + }
## Iteration #1
## Iteration #2
## Iteration #3
## > print(Sys.time())
## [1] "2011-11-06 11:06:32 PST"
## > type <- "horse"
## > type
## [1] "horse"
# Automatic "variable" substitute
# (disable with relabel=NULL)
a <- 2
b <- "Hello world!"
print(withCapture({
x <- .a.
s <- .b.
x
s
}))
## > x <- 2
## > s <- "Hello world!"
## > x
## [1] 2
## > s
## [1] "Hello world!"
}
\author{Henrik Bengtsson}
\seealso{
Internally, \code{\link[base]{eval}}() is used to evaluate the expression.
}
\keyword{utilities}
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