Files
shiny/man/renderText.Rd
Joe Cheng dde266768c Restore HTML generating functions
These functions were temporarily ripped out of Shiny and moved
to the htmltools package. We've discovered that it's safe to
keep including them in shiny; as long as the functions in shiny
and the functions in htmltools are identical, the user won't
receive a conflict warning.
2014-05-31 08:06:03 -07:00

102 lines
2.2 KiB
R

% Generated by roxygen2 (4.0.1): do not edit by hand
\name{renderText}
\alias{renderText}
\title{Text Output}
\usage{
renderText(expr, env = parent.frame(), quoted = FALSE, func = NULL)
}
\arguments{
\item{expr}{An expression that returns an R object that can be used as an
argument to \code{cat}.}
\item{env}{The environment in which to evaluate \code{expr}.}
\item{quoted}{Is \code{expr} a quoted expression (with \code{quote()})? This
is useful if you want to save an expression in a variable.}
\item{func}{A function that returns an R object that can be used as an
argument to \code{cat}.(deprecated; use \code{expr} instead).}
}
\description{
Makes a reactive version of the given function that also uses
\code{\link[base]{cat}} to turn its result into a single-element character
vector.
}
\details{
The corresponding HTML output tag can be anything (though \code{pre} is
recommended if you need a monospace font and whitespace preserved) and should
have the CSS class name \code{shiny-text-output}.
The result of executing \code{func} will passed to \code{cat}, inside a
\code{\link[utils]{capture.output}} call.
}
\examples{
isolate({
# renderPrint captures any print output, converts it to a string, and
# returns it
visFun <- renderPrint({ "foo" })
visFun()
# '[1] "foo"'
invisFun <- renderPrint({ invisible("foo") })
invisFun()
# ''
multiprintFun <- renderPrint({
print("foo");
"bar"
})
multiprintFun()
# '[1] "foo"\\n[1] "bar"'
nullFun <- renderPrint({ NULL })
nullFun()
# 'NULL'
invisNullFun <- renderPrint({ invisible(NULL) })
invisNullFun()
# ''
vecFun <- renderPrint({ 1:5 })
vecFun()
# '[1] 1 2 3 4 5'
# Contrast with renderText, which takes the value returned from the function
# and uses cat() to convert it to a string
visFun <- renderText({ "foo" })
visFun()
# 'foo'
invisFun <- renderText({ invisible("foo") })
invisFun()
# 'foo'
multiprintFun <- renderText({
print("foo");
"bar"
})
multiprintFun()
# 'bar'
nullFun <- renderText({ NULL })
nullFun()
# ''
invisNullFun <- renderText({ invisible(NULL) })
invisNullFun()
# ''
vecFun <- renderText({ 1:5 })
vecFun()
# '1 2 3 4 5'
})
}
\seealso{
\code{\link{renderPrint}} for capturing the print output of a
function, rather than the returned text value.
}