fix: fix rate sensor

Fixes `net` and `io` sensors not showing any values.

1 files changed, 2 insertions, 2 deletions

diff --git a/app/Sensor.hs b/app/Sensor.hs
index 9ef38d0..8bfed22 100644
--- a/app/Sensor.hs
+++ b/app/Sensor.hs
@@ -139,9 +139,9 @@ maxS sf = S.feedbackS 0 $ proc ((), xMax) -> do
   returnA -< (if xMax <= 0 then 0 else x / xMax', xMax')
 
 rate :: (Monad m, Num a) => S.Sensor m () a -> S.Sensor m () a
-rate sf = S.feedbackS 0 $ proc ((), x') -> do
+rate sf = S.feedbackS Nothing $ proc ((), x') -> do
   x <- sf -< ()
-  returnA -< (x - x', x)
+  returnA -< (maybe 0 ((-) x) x', Just x)
 
 data NetStat = NetStat deriving (Show)