if (FALSE) {
ui <- fluidPage(
  p("Choose a dataset to download."),
  selectInput("dataset", "Dataset", choices = c("mtcars", "airquality")),
  downloadButton("downloadData", "Download")
)
server <- function(input, output) {
  # The requested dataset
  data <- reactive({
    get(input$dataset)
  })
  output$downloadData <- downloadHandler(
    filename = function() {
      # Use the selected dataset as the suggested file name
      paste0(input$dataset, ".csv")
    },
    content = function(file) {
      # Write the dataset to the `file` that will be downloaded
      write.csv(data(), file)
    }
  )
}
shinyApp(ui, server)
}
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