Clojure macro for async callbacks

asyncmacros.clj

(ns async.macros

	"Macros to avoid callback soup, act as defer/await "

	(:use [taoensso.timbre :as timbre :only (trace debug info warn error fatal spy)]))



(defmacro let-async [bindings & body]

	(cond

		; when there are no more bindings execute the body

		(empty? bindings) `(do ~@body) 



		; a regular (not async let)

		; e.g: [:let one "hello world"]

		(= (first bindings) :let)

		(let [[_ binding-name binding-value & remaining] bindings]

			`(let [~binding-name ~binding-value]

				(let-async ~remaining ~@body))

			)



		; an async let

		:else

		(let [[binding-name binding-value & remaining] bindings]

			`(~binding-value (fn [binding-name#] 

					(let [~binding-name binding-name#]

						(let-async ~remaining ~@body))))

			)))





(defmacro async [bindings & body]

	`(fn ~bindings ~@body)

	)

Usage:

(defn ajax [url]
    (async [success-callback]
        (ajax {:success success-callback :url url})))
(let-async [ajax-response (ajax "http://google.com")
                :let formatted-ajax-request (json-load ajax-response)]
                (do-something-with formatted-ajax-request))