clojure - How do I update a record in a vector, matching certain criteria? -


i'm trying update records in vector, match criteria.

(defrecord item [id name description])  (def items   (ref [     (->item "1" "cookies" "good tasting!")     (->item "2" "blueberries" "healthy!")    ]) )

how can e.g. "set name of item "foo" id equal 1"?

i maybe need like

(dosync (commute items ???? ))

can't figure ????

i found e.g. function update-in in docs

but 1. can't find examples records, 2. not sure if can use update different field 1 i'm using query. in examples fields seem same.

the complete use case: have webservice update operation, map id of item , optional fields have updated.

i'm new clojure. implemented remove function, id, works:

(commute items #(remove (fn [x](= (:id x) id)) %))

also find id, might step in direction update:

(nth (filtered (filter #(= (:id %) id) @items)) 0)

but don't know how update record in vector...

you can use assoc make copy of record keys replaced.

(dosync  (commute items           #(mapv (fn [i]                    (if (= (:id i) "1")                      (assoc :name "foo")                      i))                  %)))

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