R 如何在上传另一数据时从shiny 中删除一项数据

为了通过最小示例来说明我的问题，让我们考虑下面的代码(这是一个完全可重现的示例).

library(shiny)

ui <- fluidPage(
  fileInput("upload", NULL, accept = c(".csv", ".tsv")),
  numericInput("n", "Rows", value = 5, min = 1, step = 1),
  tableOutput("head"),
  fileInput("upload2", NULL, accept = c(".csv", ".tsv")),
  numericInput("n2", "Rows", value = 5, min = 1, step = 1),
  tableOutput("head2")
)

server <- function(input, output, session) {
  data <- reactive({
    req(input$upload)
    
    ext <- tools::file_ext(input$upload$name)
    switch(ext,
           csv = vroom::vroom(input$upload$datapath, delim = ","),
           tsv = vroom::vroom(input$upload$datapath, delim = "\t"),
           validate("Invalid file; Please upload a .csv or .tsv file")
    )
  })
  
  output$head <- renderTable({
    head(data(), input$n)
  })
  
  data2 <- reactive({
    
    req(input$upload2)
    
    ext <- tools::file_ext(input$upload2$name)
    switch(ext,
           csv = vroom::vroom(input$upload2$datapath, delim = ","),
           tsv = vroom::vroom(input$upload2$datapath, delim = "\t"),
           validate("Invalid file; Please upload a .csv or .tsv file")
    )
  })
  
  output$head2 <- renderTable({
    tail(data2(), input$n2)
  })
  
}

shinyApp(ui, server)

该应用程序要求用户上传一个数据集，然后询问行数并显示head()个上传数据.如果用户上传另一个数据集，同样会显示它的tail.

现在我的要求是，每当shiny 的应用程序用户上传data2来显示底部行时，顶部/头部行的data应该与其head信息一起从环境中删除；反之亦然.

我try 了很多方法，比如使用observeEvent、eventReactive等，但我做不到.请提个建议.