mongodb/mongo-ruby-driver — pull request #118 by ssimeonov (2012-09-30 00:18:13+00:00)
Title: Enhance Cursor#each to comply with Ruby conventions

The convention in Ruby 1.9.2+ is that `each` called without a block should return an `Enumerator`. This is very useful in high-performance applications such as analytics systems because it enables lazy iteration through data pipelines.