I am using the built-in data type Day (Data.Time) in two ways
data PDate = PDate Day
or
type PDate Day
doesn't seem to matter. But then this doesn't work
testrec1 = PDate 2021 7 1
I always must use the "helper function" fromGregorian
testrec0 = PDate (fromGregorian 2021 7 1)
...
PDate 2021-07-01
Looking at Real World Haskell examples
data BookInfo = Book Int String [String] deriving (Show)
...
myInfo = Book 9780135072455 "Algebra of Programming" ["Richard Bird", "Oege de Moor"]
I know there's a great Haskell lesson to learn here, so why can Book take everything naked but my Day version not?
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Lawrence Bottorff
Grand Marais, MN, USA