Add new State test to the doctest too

laijonathan · Oct 28, 2019 · 2124185 · 2124185
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commit 2124185
Showing 1 changed file with 3 additions and 0 deletions.
diff --git a/src/Course/State.hs b/src/Course/State.hs
@@ -112,6 +112,9 @@ instance Applicative (State s) where
 --
 -- >>> let modify f = State (\s -> ((), f s)) in runState (modify (+1) >>= \() -> modify (*2)) 7
 -- ((),16)
+--
+-- >>> runState ((\a -> State (\s -> (a + s, 10 + s))) =<< State (\s -> (s * 2, 4 + s))) 2
+-- (10,16)
 instance Monad (State s) where
   (=<<) ::
     (a -> State s b)