Safe Haskell	Safe
Language	GHC2021

Control.XMonad.XAccum

Synopsis

data XAccum i j a = XAccum {
- runXAccum :: i -> (j, a)
}
add :: (i -> j) -> XAccum i j ()
look :: XAccum i i i

Documentation

data XAccum i j a #

Indexed Accumulator monad.

This is an indexed version of mtl's MonadAccum. Accumulator can be seen as a Writer with the extra capability of reading the result of previus tells. Or as State where modifications are limited to appends.

We fix the internal indexed monoid here to -> for simplicity, as this is the only one we need.

Constructors

XAccum
Fields runXAccum :: i -> (j, a)

Instances

Instances details

XApplicative XAccum #
Instance details Defined in Control.XMonad.XAccum Methods xpure :: forall a (p :: k). a -> XAccum p p a # (<>:) :: forall (p :: k) (q :: k) a b (r :: k). XAccum p q (a -> b) -> XAccum q r a -> XAccum p r b # xliftA2 :: forall a b c (p :: k) (q :: k) (r :: k). (a -> b -> c) -> XAccum p q a -> XAccum q r b -> XAccum p r c # (>:) :: forall (p :: k) (q :: k) a (r :: k) b. XAccum p q a -> XAccum q r b -> XAccum p r b # (<*:) :: forall (p :: k) (q :: k) a (r :: k) b. XAccum p q a -> XAccum q r b -> XAccum p r a #
XMonad XAccum #
Instance details Defined in Control.XMonad.XAccum Methods (>>=:) :: forall a b (p :: k) (q :: k) (r :: k). XAccum p q a -> (a -> XAccum q r b) -> XAccum p r b # (>>:) :: forall a b (p :: k) (q :: k) (r :: k). XAccum p q a -> XAccum q r b -> XAccum p r b # xreturn :: forall a (p :: k). a -> XAccum p p a #
Functor (XAccum i j) #
Instance details Defined in Control.XMonad.XAccum Methods fmap :: (a -> b) -> XAccum i j a -> XAccum i j b # (<$) :: a -> XAccum i j b -> XAccum i j a #

add :: (i -> j) -> XAccum i j () #

look :: XAccum i i i #