Yes, it is. I found this post by Ittay(http://www.tikalk.com/incubator/
blog/functional-programming-scala-rest-us) helpful when trying to
understand applicative functors in general, including how a type with
a monad always has at least one applicative functor.

This tutorial by Tony Morris (http://applicative-errors-
scala.googlecode.com/svn/artifacts/0.6/pdf/index.pdf) helped me
understand the specific applicative functor for ValidationNEL that
lets you accumulate errors.

On Feb 22, 12:47 am, Vlad Patryshev <vpatrys...@xxxxxxxxx> wrote:
> Hmm, curioser and curioser. Is this the case of an applicative functor that
> does not come from a monad? Have to think.
>
> Thanks,
> -Vlad
>
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> On Mon, Feb 20, 2012 at 6:17 PM, Tony Morris <tmor...@xxxxxxxxxxx> wrote:
> > The purpose of the applicative functor for Validation is to allow
> > computation to continue after failure. That is, the very existence of
> > Validation is for the purpose tipi describe. Note that there is no possible
> > corresponding monad for this (though there is one that fails and stops
> > computing).
>
> > I have code, slides, examples and all that if you're interested enough.
> > On Feb 21, 2012 10:14 AM, "Naftoli Gugenheim" <naftoli...@xxxxxxxxx>
> > wrote:
>
> >> I have an implementation of formlets for reactive-web that I've been
> >> working on lately. I'm wondering as follows: Most implementations of
> >> validation that I've seen, whether Scalaz's, Websharper's, or Lift's Box,
> >> either hold a value or an error, not both. To me however it seems that a
> >> common scenario is a warning: There's an error message that has to be
> >> displayed, perhaps the user has to go through an extra confirmation step to
> >> proceed, but you don't actually want to prevent the user from proceeding if
> >> he knows what he's doing, so it definitely holds a value too. It seems like
> >> I need my own sealed trait with three case classes. Any thoughts?