Validate All Fields in an Elm Form Using Applicatives
We have run into the problem of of having too many inputs and
map2 only being a binary function. We could make a ternary
map3 function but eventually we'll run into the same issue.
In this lesson we'll learn to write a function that will validate an arbitrary number of fields on the form, and compute an overall result that tells you whether the form is valid as a whole.