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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Do not modify this file since it was automatically generated from:
%
% eget.R
%
% by the Rdoc compiler part of the R.oo package.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\name{eget}
\alias{eget}
\alias{ecget}
\title{Gets a variable by name}
\description{
Gets a variable by name. If non-existing, the default value is returned.
}
\usage{
eget(..., coerce=TRUE, envir=parent.frame(), inherits=FALSE, mode="default",
cmdArg=FALSE)
}
\arguments{
\item{...}{Named arguments \code{name} and \code{default}, where
\code{name} must be a \code{\link[base]{character}} string and \code{default} is
an optional default value (if not given, it's \code{\link[base]{NULL}}).
Alternatively, \code{name} and \code{default} can be given as
a named argument (e.g. \code{n=42}).}
\item{coerce}{If \code{\link[base:logical]{TRUE}}, the returned value is coerced to the class
of the default value (unless \code{\link[base]{NULL}}) using \code{\link[methods]{as}}.}
\item{envir}{A \code{\link[base]{environment}} or a named \code{\link[base]{list}} where to look
for the variable. Only if \code{envir} is an \code{\link[base]{environment}}.}
\item{inherits}{A \code{\link[base]{logical}} specifying whether the enclosing frames
of the environment should be searched or not.}
\item{mode}{A \code{\link[base]{character}} string specifying the mode of the object to
retrieve. Only if \code{envir} is an \code{\link[base]{environment}}.}
\item{cmdArg}{If \code{\link[base:logical]{TRUE}}, the corresponding command-line argument
is used as the default value.}
}
\value{
Returns an object.
}
\details{
\code{ecget(...)} is short for \code{eget(..., cmdArg=TRUE)}.
}
\examples{
# Get variable 'a' if it exists, otherwise return the default value.
value <- eget("a", default=42L)
print(value) # 42L
# Short version doing the same
value <- eget(a=42L)
print(value) # 42L
# Same, but look for the variable in 'envir' (here a list)
value <- eget("a", default=42L, envir=list(a=1))
print(value) # 1L
# Get variable 'n', which defaults to command-line argument
# 'n' ('-n' or '--n'), which in turn defaults to 42L.
value <- eget(n=cmdArg(n=42L))
print(value)
# Equivalently.
value <- ecget(n=42L)
print(value)
}
\author{Henrik Bengtsson}
\seealso{
To retrieve command-line arguments, see \code{\link[R.utils]{cmdArg}}.
See also \code{\link[base]{mget}}().
}
\keyword{file}
\keyword{IO}
\keyword{internal}
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