title: shiny reactive object not found
body: <p>I think I'm missing something with respect to reactives in my Shiny app. Here's a MRE that shows my problem printing <code>y</code>.</p>
  
  <pre><code>library(shiny)
  
  ui &lt;- fluidPage(
     titlePanel("Test"),
     textAreaInput("text", "Text", "", width = "400px"),
     verbatimTextOutput("text"),
     actionButton("do", "Run"),
     textOutput("result")
     )
  
  server &lt;- function(input, output) {
    observeEvent(input$do, {
    y &lt;- reactive({
      x &lt;- ""
      t &lt;- 1
      while (t &lt; 5) {
        x &lt;- paste(input$text, x, sep=",")
        t &lt;- t + 1
      }
    })
    })
    output$result &lt;- renderPrint({y})
  }
  
  shinyApp(ui = ui, server = server)
  </code></pre>