cljs.spec.alpha/nilable

macropreviously cljs.spec/nilableEdit
(nilable pred)

Source docstring:
returns a spec that accepts nil and values satisfiying pred
Source code @ clojurescript:src/main/cljs/cljs/spec/alpha.cljc
(defmacro nilable
  [pred]
  (let [pf (res &env pred)]
    `(nilable-impl '~pf ~pred nil)))