symbol-confusion.clj

(require '[clojure.spec.test.alpha :as st])
(require '[clojure.spec.alpha :as s])
(require '[expound.alpha :as expound])

;; Two macros, one that quotes tmp-sym in the call to `st/check`...
(defmacro check1 [sym tmp-sym & spec-body]
  `(do
     (def ~tmp-sym ~sym)
     (s/fdef ~tmp-sym ~@spec-body)
     (st/check (quote ~tmp-sym))
     ))

;; ...the other that gets the syntax quoted symbol passed in.
(defmacro check2 [sym tmp-sym quoted-tmp-sym & spec-body]
  `(do
     (def ~tmp-sym ~sym)
     (s/fdef ~tmp-sym ~@spec-body)
     (st/check ~quoted-tmp-sym)
     ))

;; Expanding them gives the same results
(= (macroexpand-1 `(check1 foo foo2 :args (s/cat) :ret false?))
   (macroexpand-1 `(check2 foo foo2 `foo2 :args (s/cat) :ret false?)))

;; The function foo returns true, and we'll check it with a spec that should fail
(defn foo [] true)

;; But only `check2` actually works
(expound/explain-results (check1 foo foo2 :args (s/cat) :ret false?))
(expound/explain-results (check2 foo foo2 `foo2 :args (s/cat) :ret false?))