t.
--
-- >>> concatOf both ("pan","ama")
-- "panama"
--
-- @
-- 'concat' ≡ 'concatOf' 'folded'
-- 'concatOf' ≡ 'view'
-- @
--
-- @
-- 'concatOf' :: 'Getter' s [r]     -> s -> [r]
-- 'concatOf' :: 'Fold' s [r]       -> s -> [r]
-- 'concatOf' :: 'Iso'' s [r]       -> s -> [r]
-- 'concatOf' :: 'Lens'' s [r]      -> s -> [r]
-- 'concatOf' :: 'Traversal'' s [r] -> s -> [r]
-- @
concatOf :: Getting [r] s [r] -> s -> [r]
concatOf l = getConst #. l Const
{-# INLINE concatOf #-}


-- | Calculate the number of targets there are fo
concatOf :: Getting [r] s [r] -> s -> [r]
concatOf l = getConst #. l Const
concatOf l = getConst #. l Const