Hi Clojurians!

Please could somebody explain the code highlighted expression below to me? 
(Adapted from *The Joy of Clojure*, listing 8.9)

(defmacro with-resource [bindings close-fn & body]
>   `(let ~bindings
>      (try
>        ~@body
>        (finally
>         (~close-fn ~(bindings 0))))))


I've changed the name of the variable from binding to bindings as I 
originally thought this was calling the function binding! I've also removed 
the redundant do loop. Using macroexpand-1 on the code yields the following:

user> (macroexpand-1 '(with-resource [x 1] #(println %)))
> (clojure.core/let [x 1] (try (finally ((fn* [p1__1605#] (println 
> p1__1605#)) x))))


 It seems like the highlighted expression is indexing into the let vector 
at position 0.  Neat trick, but this doesn't seem to work when multiple 
variables are being bound by the let. So how would one modify with-resource to 
call close-fn with multiple variables?

Regards,
Ralph

 

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