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Within LTS Haskell 24.3 (ghc-9.10.2)

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1. mapState :: ((a, s) -> (b, s)) -> State s a -> State s b

   transformers	Control.Monad.Trans.State.Lazy

   Map both the return value and final state of a computation using the given function.

   • runState (mapState f m) = f . runState
     m

2. mapStateT :: (m (a, s) -> n (b, s)) -> StateT s m a -> StateT s n b

   transformers	Control.Monad.Trans.State.Lazy

   Map both the return value and final state of a computation using the given function.

   • runStateT (mapStateT f m) = f .
     runStateT m

3. runState :: State s a -> s -> (a, s)

   transformers	Control.Monad.Trans.State.Lazy

   Unwrap a state monad computation as a function. (The inverse of state.)

4. runStateT :: StateT s (m :: Type -> Type) a -> s -> m (a, s)

   transformers	Control.Monad.Trans.State.Lazy

   No documentation available.

5. withState :: (s -> s) -> State s a -> State s a

   transformers	Control.Monad.Trans.State.Lazy

   withState f m executes action m on a state modified by applying f.

   • withState f m = modify f >> m

6. withStateT :: forall s (m :: Type -> Type) a . (s -> s) -> StateT s m a -> StateT s m a

   transformers	Control.Monad.Trans.State.Lazy

   withStateT f m executes action m on a state modified by applying f.

   • withStateT f m = modify f >> m

7. evalState :: State s a -> s -> a

   transformers	Control.Monad.Trans.State.Strict

   Evaluate a state computation with the given initial state and return the final value, discarding the final state.

   • evalState m s = fst (runState m
     s)

8. evalStateT :: Monad m => StateT s m a -> s -> m a

   transformers	Control.Monad.Trans.State.Strict

   Evaluate a state computation with the given initial state and return the final value, discarding the final state.

   • evalStateT m s = liftM fst
     (runStateT m s)

9. execState :: State s a -> s -> s

   transformers	Control.Monad.Trans.State.Strict

   Evaluate a state computation with the given initial state and return the final state, discarding the final value.

   • execState m s = snd (runState m
     s)

10. execStateT :: Monad m => StateT s m a -> s -> m s

    transformers	Control.Monad.Trans.State.Strict

    Evaluate a state computation with the given initial state and return the final state, discarding the final value.

    • execStateT m s = liftM snd
      (runStateT m s)

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