when package:hxt

when :: ArrowIf a => a b b -> a b c -> a b b
hxt Control.Arrow.ArrowIf
f `when` g : when the predicate g holds, f is applied, else the identity filter this
whenNot :: ArrowIf a => a b b -> a b c -> a b b
hxt Control.Arrow.ArrowIf
f `whenNot` g : when the predicate g does not hold, f is applied, else the identity filter this
whenNotP :: ArrowIf a => a b b -> (b -> Bool) -> a b b
hxt Control.Arrow.ArrowIf
like whenP
whenP :: ArrowIf a => a b b -> (b -> Bool) -> a b b
hxt Control.Arrow.ArrowIf
shortcut: f `whenP` p = f `when` (isA p)
processBottomUpWhenNot :: (ArrowTree a, Tree t) => a (t b) (t b) -> a (t b) (t b) -> a (t b) (t b)
hxt Control.Arrow.ArrowTree
recursively transforms a whole tree by applying an arrow to all subtrees, but transformation stops when a predicte does not hold for a subtree, leaves are transformed first