ReactiveCocoa/ReactiveCocoa — pull request #932 by brow (2013-11-11 16:14:02+00:00)
Title: Behavior of -sample: before receiver sends a value

The doc is ambiguous about how `[x sample:y]` behaves if `y` sends a value before `x` does. I wasn't sure if it would send `nil` immediately, defer sending a value until `x` sent a value, or ignore the value from `y` completely. Turns out to be the last one.