title: shiny: Update input without reactives getting triggered?
body: <p>Is there any possibility to update an input without reactives getting triggered?</p>
  
  <p>Below I put a minimal example. The aim is to update the slider without the value in the main panel changing. When the slider is changed again, then it should be forwarded to dependent reactives again. </p>
  
  <p>The question and the underlying use case is similiar to the following questions: <a href="https://stackoverflow.com/questions/31851042/r-shiny-possible-issue-with-updateinput-and-reactivity">R shiny - possible issue with update***Input and reactivity</a> and <a href="https://stackoverflow.com/questions/43334913/update-selectinput-without-trigger-reactive">Update SelectInput without trigger reactive?</a>. Similiar to these questions, there is a reactive that depends on two Inputs in my use case. I want to update one of these input depending on the other, which results in the reactive getting calculated twice. However, both of these questions got around the problem by updating the input only selectively. This is not possible in my use case, since I want to have some information shown to the user by updating the input. </p>
  
  <p>If there is no possibility to update an input without reactives getting triggered, I will ask a follow-up-question focusing on my use case. </p>
  
  <p><strong>Example</strong></p>
  
  <pre><code>library(shiny)
  
  ui &lt;- fluidPage(
     titlePanel("Update Slider - Isolate reaction?"),
  
     sidebarLayout(
        sidebarPanel(
           sliderInput("bins",
                       "Number of bins:",
                       min = 1,
                       max = 50,
                       value = 30),
           actionButton("set1", "set slider 'bins'$value=20"),
           actionButton("set2", "'ISOLATED' set slider 'bins'$value=20 ")
        ),
  
        mainPanel(
           textOutput("sliderValue")
        )
     )
  )
  
  # Define server logic 
  server &lt;- function(input, output, session) {
     output$sliderValue &lt;- renderText(input$bins) 
  
     observeEvent(input$set1,{
       updateSliderInput(session,"bins",value=20)
     })
     observeEvent(input$set2,{
       ## Is there any possibility to update the slider without 'sliderValue' changing?
       #isolate does not work
       isolate(
         updateSliderInput(session,"bins",value=20 )
         )
     })
  }
  
  shinyApp(ui = ui, server = server)
  </code></pre>