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% Copyright 1995-2016 R Core Team
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% Copyright 1995-2016 R Core Team
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% Distributed under GPL 2 or later
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% Distributed under GPL 2 or later
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\name{withVisible}
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\name{withVisible}
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\alias{withVisible}
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\alias{withVisible}
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\title{Return both a value and its visibility}
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\title{Return both a Value and its Visibility}
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\description{
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\description{
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This function evaluates an expression, returning it in a two element list
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This function evaluates an expression, returning it in a two element list
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containing its value and a flag showing whether it would automatically print.
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containing its value and a flag showing whether it would automatically print.
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}
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}
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\usage{
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\usage{
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withVisible(x)
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withVisible(x)
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}
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}
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\arguments{
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\arguments{
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  \item{x}{ An expression to be evaluated. }
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  \item{x}{an expression to be evaluated.}
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}
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}
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\details{
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\details{
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  The argument is evaluated in the caller's context.
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  The argument, \emph{not} an \code{\link{expression}} object, rather
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  an (unevaluated function) \code{\link{call}}, is evaluated in the
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  caller's context.
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  This is a \link{primitive} function.
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  This is a \link{primitive} function.
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}
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}
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\value{
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\value{
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  \item{value }{The value of \code{x} after evaluation.}
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  \item{value }{The value of \code{x} after evaluation.}
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  \item{visible }{logical; whether the value would auto-print.}
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  \item{visible }{logical; whether the value would auto-print.}
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}
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}
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\seealso{\code{\link{invisible}}, \code{\link{eval}}}
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\seealso{\code{\link{invisible}}, \code{\link{eval}};
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  \code{\link{withAutoprint}()} calls \code{\link{source}()} which
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  itself uses \code{withVisible()} in order to correctly
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  \dQuote{auto print}.
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}
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\examples{
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\examples{
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x <- 1
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x <- 1
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withVisible(x <- 1) # *$visible is FALSE
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withVisible(x <- 1) # *$visible is FALSE
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x
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x
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withVisible(x)      # *$visible is TRUE
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withVisible(x)      # *$visible is TRUE