Hello everyone,
sorry for the dumb question but I'm wrapping my head around arrow just from
this morning.
Consider this toy function to swap argument of a tuple:
swapA' :: (Arrow a) => a ((b,c), (b,c)) (c,b)
swapA' = swapFirst >>> swapSecond
where
swapFirst = first $ arr snd
swapSecond = second $ arr fst
It works but requires to pass a tuple of tuple, namely ((b,c), (b,c)).
How can I explicitly pass my tuple of tuple to swapFirst so I can simply
invoke
swapA' (1,2)
and get the correct result?
ps. I know that swap can be easily and elegantly be written as:
swap = snd &&& fst
but the point of the exercise was to experiment with first, second and
arrow concatenation
Thanks in advance,
Alfredo
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