Macro
binding => var-symbol init-expr
Creates new bindings for the (already-existing) vars, with the supplied initial values, executes the exprs in an implicit do, then re-establishes the bindings that existed before.
; clojure/core.clj:1118 (defmacro binding [bindings & body] (assert-args binding (vector? bindings) "a vector for its binding" (even? (count bindings)) "an even number of forms in binding vector") (let [var-ize (fn [var-vals] (loop [ret [] vvs (seq var-vals)] (if vvs (recur (conj (conj ret `(var ~(first vvs))) (second vvs)) (next (next vvs))) (seq ret))))] `(do (. clojure.lang.Var (pushThreadBindings (hash-map ~@(var-ize bindings)))) (try ~@body (finally (. clojure.lang.Var (popThreadBindings)))))))
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