clojure - What does ^{ mean? -


in following code, have noticed ^ character before seems map data structure. ^ used for, or ^{ used for?

(ns temper.core   (:gen-class)   (:require [mount.core :as mount]))  (mount/defstate ^{:on-reload :noop}                 http-server                 :start                 (http/start                  (-> env                      (assoc :handler (lazy-run 'temper.handler 'app))                      (update :port #(or (-> env :options :port) %))))                 :stop                 (http/stop http-server))

the ^ character metadata. please see https://clojure.org/reference/reader#macrochars , https://clojure.org/reference/metadata.

^{:on-reload :noop} , (with-meta obj {:on-reload :noop}) equivalent.


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