title: Red Reactive : cannot get true value for face data
body: <p>From Red-lang book example about reactive programming, I added test button, weirdly I can get true data value for slider but not for progress bar: for this latter it's always the initial value (20%). How to get the actual value for this latter ?</p>
  
  <pre><code>        view [
              origin 0x0 space 0x0
              tab-panel 500x100 [
          "Tab 1 " [
                      p: progress 100x20 data 20% react [face/data: s/data]
                      s: slider 100x20 data 20%
  
                      button "test" [
                          vs: s/data
                          vp: p/data
                          ?? vs
                          ?? vp
                      ]
                  ]
          "Tab 2 " [
                      p: progress 100x20 20%
                      slider 100x20 data 20% [p/data: face/data]
                  ]
  
              ]
          ]
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/404Xl.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/404Xl.png" alt="enter image description here"></a></p>