twitter/scalding — pull request #929 by bholt (2014-07-01 01:40:37+00:00)
Title: REPL: Add toIterator (and related methods)

**Work in progress, do not merge**

- [ ] Refactor ad-hoc code from `snapshot` into TemporarySequenceFile class (possibly separated out into `TemporaryFile` and `TypedSequenceFile`)
- [ ] Add `toIterator` that works at least for snapshots
- If called on a TypedPipe that is not snapshotted, generate a snapshot and call `toIterator`
- Ideally would allow running simple flatMappable operations without creating new snapshots (almost working)
- `toList` and `dump` are trivially implementable from `toIterator`
- [ ] Add documentation for new functionality, including changes made in #918
- [ ] Add note about the repl to the README
- [ ] Add a "Repl Walkthrough" Wiki page