If you have that many constructors, you probably aren't pattern-matching
against the whole thing everywhere. So you could extract the few functions
that use the entire type for case analysis into a typeclass, make each
constructor its own type, and implement the typeclass:
Instead of:
something :: A -> IO ()
something A1 = putStrLn "hello"
something (A2 _) = putStrLn "world"
Use:
data A1
data A2 = A2 Int
class RelatedConst a of
something :: a -> IO ()
instance RelatedConst A1 where
something _ = putStrLn "hello"
instance RelatedConst A2 where
something _ = putStrLn "world"
Then, each declaration and instance could go in its own file.
If on the other hand, you are using lots of partial case matches
everywhere, see if there are commonalities and extract a typeclass for each
group
On Wed, Aug 23, 2017 at 6:29 PM, Adam Flott
I have a sum type with a lot of constructors and I'm not sure how to represent the type with maintainability in mind. For example,
data A = A1 | A2 Int | A3 Text Int32 Bool | ... | A100 Bool
Every inner type is concrete. There are 100+ constructors with no sign of ever getting reduced.
What technique would you recommend to keep the sum type approach but not having to define them all in one spot? I'm thinking 1 inner type + 1 function to construct per file (if that's possible). _______________________________________________ Haskell-Cafe mailing list To (un)subscribe, modify options or view archives go to: http://mail.haskell.org/cgi-bin/mailman/listinfo/haskell-cafe Only members subscribed via the mailman list are allowed to post.