lhs test ======== `unsplit` is an arrow that takes a pair of values and combines them to return a single value: ``` {.sourceCode .literate .haskell} unsplit :: (Arrow a) => (b -> c -> d) -> a (b, c) d unsplit = arr . uncurry -- arr (\op (x,y) -> x `op` y) ``` `(***)` combines two arrows into a new arrow by running the two arrows on a pair of values (one arrow on the first item of the pair and one arrow on the second item of the pair). f *** g = first f >>> second g Block quote: > foo bar