Formlets ever had cascade validation: data Item= Item{ name ::String, quantity, price :: Int} Item <$> <*> inputString `validate` nonEmpty <*> inputInt <*> inputInt `validate` ( \item -> do if theUniverseIsSpanding then do if name item == "carrots" && price=="10" then fail "we don´t like 10 cent carrots in an expanding universe" else if..... 2014-08-14 11:41 GMT+02:00 Tom Ellis < tom-lists-haskell-cafe-2013@jaguarpaw.co.uk>:
On Thu, Aug 14, 2014 at 11:28:53AM +0200, Wojtek Narczyński wrote:
On 14.08.2014 09:19, Tom Ellis wrote:
On Wed, Aug 13, 2014 at 05:21:28PM -0700, John Lato wrote:
On Wed, Aug 13, 2014 at 4:21 PM, Tom Ellis
data LineItem = LineItem { name :: Maybe String , quantity :: Maybe Quantity , price :: Maybe Price }
Rather than this definition, what about something like:
data LineItemF f = LineItem { name :: f String , quantity :: f Quantity , price :: f Price } It seems Wojtek already objected to this approach, though perhaps that objection could be overcome
Hmm, perhaps like this
LineItemFi = LineItemFi { name :: StringFi , quantity :: QuantityFi , price :: PriceFi }
data LineItemUi f = LineItemUi { name :: StringUi , quantity :: QuantityUi , price :: PriceUi }
You didn't use f there. _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
-- Alberto.