Alpha - subject to change.
Returns a transient map that doesn't contain a mapping for key(s).
;; dissoc! works on a transient map
;; WARNING: Below is an example of what is called "bashing in place" of
;; a transient, and is _NOT_ the correct way to use transients. See assoc!
;; examples for some discussion of the reason.
(let [my-map (transient {:x 1 :y 2 :z 3})]
(dissoc! my-map :x) ; mistake is to use my-map below, not dissoc! return val
(persistent! my-map)) ; returns persistent map {:y 2 :z 3}
;; Here is a correct way to do the operation described above:
(let [my-map (transient {:x 1 :y 2 :z 3})
x (dissoc! my-map :x)] ; after this, don't use my-map again, only x
(persistent! x)) ; returns persistent map {:y 2 :z 3}
Source
clojure/core.clj:2964
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(defn dissoc!
"Alpha - subject to change.
Returns a transient map that doesn't contain a mapping for key(s)."
{:added "1.1"
:static true}
([^clojure.lang.ITransientMap map key] (.without map key))
([^clojure.lang.ITransientMap map key & ks]
(let [ret (.without map key)]
(if ks
(recur ret (first ks) (next ks))
ret))))
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