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Merge pull request #523 from mb64/hasio-statet

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Implement HasIO for StateT
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Niklas Larsson 2020-08-18 14:02:02 +02:00 committed by GitHub
commit 84ae9d7c6e
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libs/base/Control/Monad/State.idr
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@ -58,6 +58,10 @@ implementation (Monad f, Alternative f) => Alternative (StateT st f) where
empty = lift empty
(ST f) <|> (ST g) = ST (\st => f st <|> g st)
public export
implementation HasIO m => HasIO (StateT stateType m) where
liftIO io = ST $ \s => liftIO $ io_bind io $ \a => pure (a, s)
||| Apply a function to modify the context of this computation
public export
modify : MonadState stateType m => (stateType -> stateType) -> m ()