aphyr/riemann — pull request #179 by banjiewen (2013-03-29 13:52:33+00:00)
Title: Ensure that (:streams core) is always a vec.

Clojure.core/concat always returns a LazySeq, not a vec, and LazySeq has some
[synchronized badness](1).

[1]: https://github.com/clojure/clojure/blob/master/src/jvm/clojure/lang/LazySeq.java#L59