async fail.cljs

(ns chestnut-test2.core
  (:require
   [cljs.core.async :as async :refer [chan close! <! >! put! timeout alts! to-chan]])
  (:require-macros
   [cljs.core.async.macros :refer [go go-loop]]))

(def c (to-chan [1 2 3 4])) ;;works

(go (print (<! c))) ;;works

(go (.log js/console (alts! [c]))) ;;error

thrown error.txt

Uncaught TypeError: Cannot call method 'call' of undefined
core.cljs[eval118] [147]	anonymous
core.cljs[eval118] [162]	anonymous
core.cljs[eval118] [179]	cljs.core.async.impl.dispatch.run.call.state_machine__15034__auto____1
core.cljs[eval118] [196]	cljs.core.async.impl.dispatch.run.call.state_machine__15034__auto__
ioc_helpers.js [57]	run_state_machine
ioc_helpers.js [59]	run_state_machine_wrapped
core.cljs[eval118] [207]	anonymous
dispatch.js [16]	process_messages
dispatch.js [37]	cljs.core.async.impl.dispatch.message_channel.port1.onmessage