twitter/util — pull request #92 by mosesn (2014-03-22 23:57:07+00:00)
Title: util-core: Fixes detachable semantics with ConstFuture

## Motivation
Promise.attached on ConstFutures didn't work as you'd expect, which would be that it would fulfil the Promise and then detach it.

## Modification
Changes the parent.respond to execute outside of the class initialization.

## Result
Promise.attached is significantly easier to reason about with ConstFutures.