hadley/adv-r — pull request #517 by sbgraves237 (2014-05-28 18:25:11+00:00)
Title: description does not match diagram

re. diagrams/environments.png/where-ex.png"): The description said 'b' was the second environment and 'c' was absent. The image showed 'c' but not 'b'. This patch fixes that obvious error.