Clojure Spec and Human Readable Error Messages

[David Simmons]

Hi All.

I've just come back to Clojure (after being away for a few years) and I'm incredibly impressed with how things have moved on. I particuarly like Clojure Spec but I'm struggling to understand how I can convert coercion erros to a human friendly for for end users to understand on a website - i..e user submits a form and gets an error back they can understand.

My Google Foo doesn't appear to have helped but I can't believe I'm the only one to find this a problem (or maybe I don't fully understand spec).

any help gratefully received.

cheers

Dave

[John Shaffer]

The phrase library can create human-readable error messages:

https://github.com/alexanderkiel/phrase

I've been working on something for a more natural (to me) approach, with the ability to define error messages in-line with the predicate. E.g.,

(s/defop max-length [n]

  (sf/validator

   #(>= n (count %))

   (str "Must be " n " characters or less.")))

I got this working with spec-alpha2, but my plan was to write some reforms helpers, and I don't think there is any alpha2 support in ClojureScript. It seems a lot harder to write specs for the shipping version of spec, but I'll probably give it a shot this weekend.

[David Simmons]

Many thanks John.

I'll check out phrase. If you do get something working I'd love to see it as your approach seems the simplest to me.

cheers

Dave