Support trailing metadata in defn

[borkdude]

(defn foo
  ([])
  ([_ _])
  {:x true})

Merely for compatibility

[borkdude]

For future reference, we started supporting this because the omniconf library used this. I found this back using grasp. It's actually the only library in my entire .m2 folder which uses the trailing metadata map.

(ns trailing-meta)

(require
 '[clojure.core.specs.alpha :as specs]
 '[clojure.spec.alpha :as s]
 '[grasp.api :as g])

(s/def ::defn (s/cat :defn #{'defn} :args ::specs/defn-args))
(s/def ::defn-trailing-attr-map (s/and ::defn (fn [conformed]
                                                (->> conformed
                                                     :args :fn-tail second :attr-map))))

(def matches (g/grasp "/Users/borkdude/.m2" ::defn-trailing-attr-map))

;; (prn (s/conform ::defn-trailing-attr-map (first matches)))
(run! (comp prn meta) matches)

{:line 272, :column 1, :url "jar:file:/Users/borkdude/.m2/repository/com/grammarly/omniconf/0.4.3/omniconf-0.4.3.jar!/omniconf/core.clj"}
{:line 312, :column 1, :url "jar:file:/Users/borkdude/.m2/repository/com/grammarly/omniconf/0.4.3/omniconf-0.4.3.jar!/omniconf/core.clj"}
{:line 372, :column 1, :url "jar:file:/Users/borkdude/.m2/repository/com/grammarly/omniconf/0.4.3/omniconf-0.4.3.jar!/omniconf/core.clj"}
{:line 390, :column 1, :url "jar:file:/Users/borkdude/.m2/repository/com/grammarly/omniconf/0.4.3/omniconf-0.4.3.jar!/omniconf/core.clj"}