clojure - How do i get a modified Set after updating element for a specific key? -

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i have set of objects

(def books #{{:isbn 1 :title "programming clojure"}              {:isbn 2 :title "joy of clojure"}              {:isbn 3 :title "clojure in action"}})

how update object having given key (:isbn) , return modified set?

(??? books :isbn {:isbn 1 :title "programming clojure" :author "halloway"})

in java, equality can defined using isbn , element can directly added set. idiomatic way of doing in clojure?

if want kind of updates, should have associative structure. can turn set 1 , again:

(-> (group-by :isbn books)     (assoc-in [1 0 :author] "halloway") ; 1 isbn, 0 means "first"     vals      (->> (map first))      set)

this code assumes :isbn unique (since said "key"). turns set map :isbn values sequences of corresponding records, updates first record :isbn 1 author, mangles set.


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