This is a situation where I reach for eval. Construct your reify call as if
you were inside a macro, but instead of returning data from the macro, call
(eval form). The call to reify will be slow (and could cause permgen
problems), but if you wrap the form in a function you can cache the
function and avoid that problem. Something like:


(let [cache (atom {})]
  (defn implement-at-runtime [interface-name method-name & body]
    (if-let [result (@cache [interface-name method-name body])]
      (result)
      (let [f (eval `(fn []
                       (reify
                         ~interface-name
                         (~method-name ~@body))))]
        (swap! cache assoc [interface-name  method-name body] f)
        (f)))))

@(implement-at-runtime 'clojure.lang.IDeref 'deref '[this] 42)
;; returns 42

Timothy

On Fri, Apr 24, 2015 at 8:14 AM, Steven Deobald <ste...@nilenso.com> wrote:

> Okay, Brian. I'll bite. :)
>
> I don't have the answer for you, but I'm definitely curious what your use
> case is. Whatcha upto?
>
> Steven Deobald -- ⌀ -- nilenso.com
>
> On Fri, Apr 24, 2015 at 7:18 PM, Brian Guthrie <btguth...@gmail.com>
> wrote:
>
>> Hi all,
>>
>> Is there a good way to reify protocols programmatically, i.e., by passing
>> data structures rather than dropping down into a macro? reify bottoms out
>> in reify*, which doesn't help much.
>>
>> Thanks,
>>
>> Brian
>>
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zero–they had no way to indicate successful termination of their C
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