takes a val from port. Must be called inside a (go ...) block. Will
return nil if closed. Will park if nothing is available.
Returns true unless port is already closed
Source
(defn<!"takes a val from port. Must be called inside a (go ...) block. Will\n return nil if closed. Will park if nothing is available.\n Returns true unless port is already closed"[port](throw(js/Error."<! used not in (go ...) block")))