I'm getting an error from spec that I don't understand. Maybe someone can help me. The following example, which I've based on an example in https://clojure.org/guides/spec, works fine, and valid? returns true.

(s/valid? (s/keys :req [::first-name ::last-name ::email]
                  :opt [::phone])
          {::first-name "Bugs"
           ::last-name "Bunny"
           ::email ""})

(let [sss '(clojure.spec.alpha/keys
            :req [:clojure-rte.genus-spec-test/first-name
                  :clojure-rte.genus-spec-test/last-name
                  :clojure-rte.genus-spec-test/email]
            :opt [:clojure-rte.genus-spec-test/phone])]
  (s/valid? sss
          {::first-name "Bugs"
           ::last-name "Bunny"
           ::email ""}))

Execution error (ClassCastException) at (REPL:1).
null

@jimka.issy An s-expression is not yet a spec. I would assume most people would write a macro for creating specs programmatically

Yes, but you need to understand more about how spec works

valid? works on spec objects

Spec forms need to be evaluated into spec objects first

In the case above, you could do that with eval

or generate the form with a macro

Even so, you’re still leaning on eval

yep

Made some fun macros the other day:

(def kws (map keyword (repeatedly gensym)))

(defmacro cat [& preds]
  `(clojure.spec.alpha/cat [email protected](interleave kws
                                         (map expand-query preds))))

Spec 2 has a lot more tools for all this stuff

defop right?

That’s one

any docs I could read yet?

The wiki pages if you haven’t seen those

But not everything is in there and it’s missing a lot of the internal design

I'll just wait, no hurry

There is now an intermediate map data form now that you can work on directly

But will almost certainly change

Working with maps is a lot easier than writing macros (since macros beget more macros)

Some day rich or I will do a talk about the internals - there are several interesting aspects of it

Looking forward

macros wont help in this case. the origin of my spec is not sitting in an evaluation position.

thus, eval

evaluating a spec form gives you a spec object