LabREPL Unified update model notes and exercises

labrepl-unified-updates.clj

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;; Atoms

;; Using swap! and merge-with on a map
;; the trick is to put merge-with inside a function.

(def m (atom {:a 1}))
;=> #'user/m

user> (swap! m #(merge-with + % {:a 2}))
;=> {:a 3}