   save hist
 
 
+ENABLE_SERVER_HISTOCACHE = true 
+
 window.Histogram = ReactiveComponent
   displayName : 'Histogram'
 

            done: (positions) =>   
              return if !@isMounted()
              if Object.keys(positions).length != 0 && @current_request == histocache_key
                @local.histocaches = 
                  hash: histocache_key
                  positions: positions


    # extraction from @try_histocache
    proposal = fetch(@props.proposal)
    histocache_key = @histocache_key()
    if ENABLE_SERVER_HISTOCACHE && proposal.histocache?[histocache_key]
      if histocache_key != @local.histocache?.hash
        @local.histocache =
          hash: histocache_key 
