store/[org.clojure/clojure "1.8.0"] clj::clojure.core/set!

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Docstring
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  Used to set thread-local-bound vars, Java object instance
fields, and Java class static fields.

Example 1

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(set! var-symbol expr)

Example 2

Edit
(set! *warn-on-reflection* true)

Uses on crossclj