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Explicit method impls for MonadState and MonadWriter Product instances #172

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Merged
sjshuck merged 1 commit into from
Oct 25, 2025
+3 −1
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Explicit method impls for MonadState and MonadWriter Product instances #172

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1 change: 1 addition & 0 deletions Control/Monad/State/Class.hs
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Expand Up @@ -197,3 +197,4 @@ instance MonadState s m => MonadState s (SelectT r m) where
instance (MonadState s m, MonadState s n) => MonadState s (Product m n) where
get = Pair get get
put s = Pair (put s) (put s)
state sas = Pair (state sas) (state sas)
3 changes: 2 additions & 1 deletion Control/Monad/Writer/Class.hs
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Expand Up @@ -208,6 +208,7 @@ instance
pass = Accum.liftPass pass

instance (MonadWriter w m, MonadWriter w n) => MonadWriter w (Product m n) where
tell w = Pair (tell w) (tell w)
writer aw = Pair (writer aw) (writer aw)
tell w = Pair (tell w) (tell w)
listen (Pair ma na) = Pair (listen ma) (listen na)
pass (Pair maf naf) = Pair (pass maf) (pass naf)