simple usage of halt-when with clojure core.async

gistfile1.txt

+user=> (def c (>/chan 1 (halt-when even?)))
#'user/c
+user=> (>/take! c println)
nil
+user=> (>/put! c 1)
true1

+user=> (>/take! c println)
nil
+user=> (>/put! c 3)
true
user=> 3

+user=> (>/take! c println)
nil
+user=> (>/put! c 2)
true
nil
+user=> (>/take! c println)
nil
nil

gistfile2.txt

+user=> (def c (>/chan 1 (halt-when even? (fn [x y] (println "halted on" x "with" y)))))
#'user/c
+user=> (>/take! c (fn [x] (println \newline "x:" x)))
nil
+user=> (>/put! c 1)
true
user=> 
 x: 1

+user=> (>/put! c 3)
true
+user=> (>/take! c (fn [x] (println \newline "x:" x)))

 x: 3
nil
+user=> (>/take! c (fn [x] (println \newline "x:" x)))
nil
+user=> (>/put! c 2)
halted on #object[clojure.core.async.impl.buffers.FixedBuffer 0x2b9bbaa8 clojure.core.async.impl.buffers.FixedBuffer@2b9bbaa8] with 2
true
user=> 
 x: nil