in src/main/scala/com/twitter/stitch/Arrow.scala [1751:1766]
override def run[T2 <: T, V](
ts: ArrayBuffer[Try[T2]],
ls: ArrayBuffer[Locals],
tail: Arrow[U, V]
): Stitch[ArrayBuffer[Try[V]]] = {
val ss = ts.asInstanceOf[ArrayBuffer[Stitch[U]]]
var i = 0
while (i < ts.length) {
ss(i) = ts(i) match {
case Throw(e) if f.isDefinedAt(e) => Stitch.app(f, e)
case t => Stitch.const(t.asInstanceOf[Try[U]])
}
i += 1
}
Stitch.transformSeq(ss, ls, tail)
}