Can `validate` return a nonempty list of errors?

[andys8]

validate returns type List error for the Err case of Result.

validate :
    Validator error subject
    -> subject
    -> Result (List error) (Valid subject)

Issue

How to handle Err [ ]? Can we get rid of it?

Possible solution

Use a non-empty-list of error to represent the error case.

• https://package.elm-lang.org/packages/mgold/elm-nonempty-list/latest
• Own custom non empty list type, e.g. (firstError, otherErrors) : (error, List error)