*eval*

dynamic var

since v1.10.191

Edit

Source docstring:

Runtime environments may provide a way to evaluate ClojureScript
forms. Whatever function *eval* is bound to will be passed any forms which
should be evaluated.

(defonce
  ^{:dynamic true}
  *eval*
  (fn [_]
    (throw (js/Error. "cljs.core/*eval* not bound"))))

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