swap!

function

since v0.0-927

clojure.core/swap!

Edit

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Details:

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See Also:

• atom
• reset!

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Source docstring:

Atomically swaps the value of atom to be:
(apply f current-value-of-atom args). Note that f may be called
multiple times, and thus should be free of side effects.  Returns
the value that was swapped in.

(defn swap!
  ([a f]
   (if (instance? Atom a)
     (reset! a (f (.-state a)))
     (-swap! a f)))
  ([a f x]
   (if (instance? Atom a)
     (reset! a (f (.-state a) x))
     (-swap! a f x)))
  ([a f x y]
   (if (instance? Atom a)
     (reset! a (f (.-state a) x y))
     (-swap! a f x y)))
  ([a f x y & more]
   (if (instance? Atom a)
     (reset! a (apply f (.-state a) x y more))
     (-swap! a f x y more))))

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