DA.Either Samples
App Development3 posts345 views9 likesLast activity Sep 2020
CA
carleslabonOP
Sep 2020Hello, good evening! I would like to ask on how we could implement DA.Either functions, since I’m having a hard time finding some sample codes.
Thanks!
GA
Gary_Verhaegen
Sep 2020Hi @carleslabon,
Implementing them yourself based on pattern matching may be a good learning experience. For an example syntax, if you wanted to convert an Either to a list, with an empty list for a Right and a single-element list for a Left, you would write:
keepLeft: Either a b -> [a]
keepLeft e = case e of
Right _ -> []
Left a -> [a]
If you’re not after the exercise but just want to see how we did it, you can simply look at the source code for the DA.Either module.
CA
carleslabon
Sep 2020