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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/options.R
\name{with_options}
\alias{with_options}
\alias{local_options}
\title{Options}
\usage{
with_options(new, code)
local_options(.new = list(), ..., .local_envir = parent.frame())
}
\arguments{
\item{new, .new}{\verb{[named list]}\cr New options and their values}
\item{code}{\code{[any]}\cr Code to execute in the temporary environment}
\item{...}{Additional options and their values}
\item{.local_envir}{\verb{[environment]}\cr The environment to use for scoping.}
}
\value{
\code{[any]}\cr The results of the evaluation of the \code{code}
argument.
}
\description{
Temporarily change global options.
}
\examples{
# number of significant digits to print
getOption("digits")
# modify temporarily the number of significant digits to print
with_options(list(digits = 3), getOption("digits"))
with_options(list(digits = 3), print(pi))
# modify temporarily the character to be used as the decimal point
getOption("digits")
with_options(list(OutDec = ","), print(pi))
# modify temporarily multiple options
with_options(list(OutDec = ",", digits = 3), print(pi))
# modify, within the scope of the function, the number of
# significant digits to print
print_3_digits <- function(x) {
# assign 3 to the option "digits" for the rest of this function
# after the function exits, the option will return to its previous
# value
local_options(list(digits = 3))
print(x)
}
print_3_digits(pi) # returns 3.14
print(pi) # returns 3.141593
}
\seealso{
\code{\link{withr}} for examples
\code{\link[=options]{options()}}
}
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