#12772: (type f1 ~> f2 = forall a. f1 a -> f2 a) to core libraries -------------------------------------+------------------------------------- Reporter: Iceland_jack | Owner: Type: feature request | Status: new Priority: normal | Milestone: Component: Build System | Version: 8.0.1 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Description changed by Iceland_jack: @@ -12,33 +12,33 @@ - unLift :: Applicative f - => Lift f a -> f a - mapLift :: (f a -> g a) - -> Lift f a -> Lift g a - mapFreeT :: (Functor f, Functor m) - => (forall a. m a -> m' a) - -> FreeT f m a -> FreeT f m' a - vmap :: (a -> a') - -> Vec a n -> Vec a' n - liftIO :: MonadIO m - => IO a -> m a - hoist :: Monad m - => (forall a. m a -> n a) - -> t m b -> t n b - trans :: (Monad m, Monad m') - => (forall a. m a -> m' a) - -> Bundle m v a -> Bundle m' v a - process :: Monad m - => (forall a. k a -> i -> a) - -> MachineT m k o -> ProcessT m i o - runAlt :: Alternative g - => (forall x. f x -> g x) - -> Alt f a -> g a - hoistAlt :: (forall a. f a -> g a) - -> Alt f b -> Alt g b - fromCurried :: Functor f - => (forall a. k a -> Curried f h a) - -> Day f k b -> h b - hoistScope :: Functor f - => (forall x. f x -> g x) - -> Scope b f a -> Scope b g a - - haddockWithGhc :: (forall a. [Flag] -> Ghc a -> IO a) -> [String] -> IO () + unLift :: Applicative f + => Lift f a -> f a + mapLift :: (f a -> g a) + -> Lift f a -> Lift g a + mapFreeT :: (Functor f, Functor m) + => (forall a. m a -> m' a) + -> FreeT f m a -> FreeT f m' a + vmap :: (a -> a') + -> Vec a n -> Vec a' n + liftIO :: MonadIO m + => IO a -> m a + hoist :: Monad m + => (forall a. m a -> n a) + -> t m b -> t n b + trans :: (Monad m, Monad m') + => (forall a. m a -> m' a) + -> Bundle m v a -> Bundle m' v a + process :: Monad m + => (forall a. k a -> i -> a) + -> MachineT m k o -> ProcessT m i o + runAlt :: Alternative g + => (forall x. f x -> g x) + -> Alt f a -> g a + hoistAlt :: (forall a. f a -> g a) + -> Alt f b -> Alt g b + fromCurried :: Functor f + => (forall a. k a -> Curried f h a) + -> Day f k b -> h b + hoistScope :: Functor f + => (forall x. f x -> g x) + -> Scope b f a -> Scope b g a + haddockWithGhc :: (forall a. [Flag] -> Ghc a -> IO a) + -> [String] -> IO () @@ -61,33 +61,33 @@ - unLift :: Applicative f - => Lift f ~> f - mapLift :: f ~> g - -> Lift f ~> Lift g - mapFreeT :: (Functor f, Functor m) - => m ~> m' - -> FreeT f m ~> FreeT f m' - vmap :: (a -> a') - -> Vec a ~> Vec a' - liftIO :: MonadIO m - => IO ~> m - hoist :: Monad m - => m ~> n - -> t m ~> t n - trans :: (Monad m, Monad m') - => m ~> m' - -> Bundle m v ~> Bundle m' v - process :: Monad m - => k ~> (i -> ) - -> MachineT m k ~> ProcessT m i - runAlt :: Alternative g - => f ~> g - -> Alt f ~> g - hoistAlt :: f ~> g - -> Alt f ~> Alt g - fromCurried :: Functor f - => (k ~> Curried f h) - -> Day f k ~> h - hoistScope :: Functor f - => f ~> g - -> Scope b f ~> Scope b g - - haddockWithGhc :: ([Flag] -> Ghc ~> IO) -> [String] -> IO () + unLift :: Applicative f + => Lift f ~> f + mapLift :: f ~> g + -> Lift f ~> Lift g + mapFreeT :: (Functor f, Functor m) + => m ~> m' + -> FreeT f m ~> FreeT f m' + vmap :: (a -> a') + -> Vec a ~> Vec a' + liftIO :: MonadIO m + => IO ~> m + hoist :: Monad m + => m ~> n + -> t m ~> t n + trans :: (Monad m, Monad m') + => m ~> m' + -> Bundle m v ~> Bundle m' v + process :: Monad m + => k ~> (i -> ) + -> MachineT m k ~> ProcessT m i + runAlt :: Alternative g + => f ~> g + -> Alt f ~> g + hoistAlt :: f ~> g + -> Alt f ~> Alt g + fromCurried :: Functor f + => k ~> Curried f h + -> Day f k ~> h + hoistScope :: Functor f + => f ~> g + -> Scope b f ~> Scope b g + haddockWithGhc :: ([Flag] -> Ghc ~> IO) + -> [String] -> IO () New description: Is this something that belongs to core libraries (it has other names in the wild, `:~>`, `Natural`..) {{{#!hs type f1 ~> f2 = forall a. f1 a -> f2 a }}} I use it all the time and end up redefining it (it is such a short type that maybe it's not worth it, ‘Fairbairn threshold’ something something) {{{#!hs unLift :: Applicative f => Lift f a -> f a mapLift :: (f a -> g a) -> Lift f a -> Lift g a mapFreeT :: (Functor f, Functor m) => (forall a. m a -> m' a) -> FreeT f m a -> FreeT f m' a vmap :: (a -> a') -> Vec a n -> Vec a' n liftIO :: MonadIO m => IO a -> m a hoist :: Monad m => (forall a. m a -> n a) -> t m b -> t n b trans :: (Monad m, Monad m') => (forall a. m a -> m' a) -> Bundle m v a -> Bundle m' v a process :: Monad m => (forall a. k a -> i -> a) -> MachineT m k o -> ProcessT m i o runAlt :: Alternative g => (forall x. f x -> g x) -> Alt f a -> g a hoistAlt :: (forall a. f a -> g a) -> Alt f b -> Alt g b fromCurried :: Functor f => (forall a. k a -> Curried f h a) -> Day f k b -> h b hoistScope :: Functor f => (forall x. f x -> g x) -> Scope b f a -> Scope b g a haddockWithGhc :: (forall a. [Flag] -> Ghc a -> IO a) -> [String] -> IO () newtype Alt f a = Alt { _runAlt :: forall g. Alternative g => (forall x. f x -> g x) -> g a } newtype Builder = Builder (forall r. BuildStep r -> BuildStep r) data Zipper t a = Zipper (forall b. Seq b -> t b) {-# UNPACK #-} !Int !(Seq a) class MonadCatch m => MonadMask m where mask :: ((forall a. m a -> m a) -> m b) -> m b }}} becomes {{{#!hs unLift :: Applicative f => Lift f ~> f mapLift :: f ~> g -> Lift f ~> Lift g mapFreeT :: (Functor f, Functor m) => m ~> m' -> FreeT f m ~> FreeT f m' vmap :: (a -> a') -> Vec a ~> Vec a' liftIO :: MonadIO m => IO ~> m hoist :: Monad m => m ~> n -> t m ~> t n trans :: (Monad m, Monad m') => m ~> m' -> Bundle m v ~> Bundle m' v process :: Monad m => k ~> (i -> ) -> MachineT m k ~> ProcessT m i runAlt :: Alternative g => f ~> g -> Alt f ~> g hoistAlt :: f ~> g -> Alt f ~> Alt g fromCurried :: Functor f => k ~> Curried f h -> Day f k ~> h hoistScope :: Functor f => f ~> g -> Scope b f ~> Scope b g haddockWithGhc :: ([Flag] -> Ghc ~> IO) -> [String] -> IO () newtype Alt f a = Alt { _runAlt :: forall g. Alternative g => (f ~> g) -> g a } newtype Builder = Builder (BuildStep ~> BuildStep) data Zipper t a = Zipper (Seq ~> t) {-# UNPACK #-} !Int !(Seq a) class MonadCatch m => MonadMask m where mask :: ((m ~> m) -> m b) -> m b }}} these examples are pretty similar. ---- Same for {{{#!hs mapBlock :: (forall e x. n e x -> n' e x) -> Block n e x -> Block n' e x mapGraph :: (forall e x. n e x -> n' e x) -> Graph n e x -> Graph n' e x mapGraphNodes1 :: (forall e x. CmmNode e x -> CmmNode e x) -> CmmGraph -> CmmGraph foldCat :: (Catenated t, Category s) => (forall a b. r a b -> s a b) -> t r a b -> s a b mapCat :: Catenated t => (forall a b. r a b -> s a b) -> t r a b -> t s a b newtype Copastro p a b = Copastro { runCopastro :: forall r. Costrong r => (forall x y. p x y -> r x y) -> r a b } newtype CopastroSum p a b = CopastroSum { runCopastroSum :: forall r. Cochoice r => (forall x y. p x y -> r x y) -> r a b } }}} vs {{{#!hs type f1 ~~> f2 = forall a b. f1 a b -> f2 a b mapBlock :: n ~~> n' -> Block n ~~> Block n' mapGraph :: n ~~> n' -> Graph n ~~> Graph n' mapGraphNodes1 :: CmmNode ~~> CmmNode -> CmmGraph -> CmmGraph foldCat :: (Catenated t, Category s) => r ~~> s -> t r ~~> s mapCat :: Catenated t => r ~~> s -> t r ~~> t s newtype Copastro p a b = Copastro { runCopastro :: forall r. Costrong r => (p ~~> r) -> r a b } newtype CopastroSum p a b = CopastroSum { runCopastroSum :: forall r. Cochoice r => (p ~~> r) -> r a b } }}} -- -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12772#comment:5 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler