shiny/man/makeReactiveBinding.Rd

\name{makeReactiveBinding}
\alias{makeReactiveBinding}
\title{Make a reactive variable}
\usage{
  makeReactiveBinding(symbol, env = parent.frame())
}
\arguments{
  \item{symbol}{A character string indicating the name of
  the variable that should be made reactive}

  \item{env}{The environment that will contain the reactive
  variable}
}
\value{
  None.
}
\description{
  Turns a normal variable into a reactive variable, that
  is, one that has reactive semantics when assigned or read
  in the usual ways. The variable may already exist; if so,
  its value will be used as the initial value of the
  reactive variable (or \code{NULL} if the variable did not
  exist).
}
\examples{
\dontrun{
a <- 10
makeReactiveBinding("a")
b <- reactive(a * -1)
observe(print(b()))
a <- 20
}
}