I'm experimenting with using the analyzer for some more sophisticated macros, including a CPS transform and control constructs. During interactive development, I discovered that the analyzer is incorrectly merging metadata on vars when redefining them. This patch changes redef's to replace, rather than merge, existing var metadata.

The patch does not include a test, since the tests don't currently muck with the analyzer directly. Here's some code you can play with in your repl:

(require '[cljs.analyzer :as ana])
(require '[cljs.compiler :as comp])

(def env (ana/empty-env))

(defn show-foo [form]
  (ana/analyze env form)
  (-> @ana/namespaces (get 'cljs.user) :defs (get 'x) :foo))

(show-foo '(def ^{:foo 1} x 1))

(show-foo '(def ^{:foo 2} x 1))

(show-foo '(def x 1))  ; before patch, this returns 2. After patch, nil.