Whoops. Misclick. Sorry

Here again:

(def *deferred-bindings* {})

(defmacro do-binding
  [& body]
  `(with-bindings *deferred-bindings*
     ~@body))

(defmacro bind-later
  [bindings & body]
  (let [vars   (map (fn [v] `(var ~v)) (take-nth 2 bindings))
        values (take-nth 2 (next bindings))]
    `(binding [*deferred-bindings* (merge *deferred-bindings*
                                          ~(zipmap vars values))]
       ~@body)))

user=> (def a "outer a")
#'user/a
user=> (bind-later [a "inner a"] (println a) (do-binding (println a)))
outer a
inner a
nil
user=> (def b "outer b")
#'user/b
user=> (bind-later [a "inner a"] (println a) (bind-later [b "inner b"]
(println b) (do-binding (println a) (println b)))
)
outer a
outer b
inner a
inner b
nil

Nested invocations merge together. However I haven't checked all the
edge cases.

And always with binding: beware thread boundaries. But I think you
know the drill. ;)

Sincerely
Meikel

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