($>) is analogous to (*>) not by dropping the f in the first position, but the f in the second, as proposed.

(*>) :: Applicative f => f a -> f b -> f b

($>) :: Functor f => f a -> b -> f b

It is unfortunate that (*>) is not equivalent to (flip (<*)), but it is a special case where breaking the "flipped characters" convention is useful for the sake of Applicative's convention to gather effects from left to right. It is nice that ($>) adheres to the flipped characters convention as well as being analogous to (*>).

-- Dan Burton

On Sun, Dec 8, 2013 at 9:22 AM, Stijn van Drongelen <rhymoid@gmail.com> wrote:

> Data.Functor has <$> and <$, but not $>, which should be a flipped version
> of <$, analogous to <*>, <*, and *> in Control.Applicative.

Whoa there, it's not at all analogous. Your wording is almost suggesting that <* is a flipped *>, but beyond that, they are uncomparable to begin with.

Applicative functors:

(<*>) :: Applicative f => f (a -> b) -> f a -> f b

(<*) :: Applicative f => f a -> f b -> f a
(*>) :: Applicative f => f a -> f b -> f b

Removing the `f` in the first position, you'd get an honest analogue for any functor:

(<$>) :: Functor f => (a -> b) -> f a -> f b

(<$) :: Functor f => a -> f b -> f a
($>) :: Functor f => a -> f b -> f b

Here, I don't see how ($>) could be anything else than `const id`.

Or am I missing something here?

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