middleman/middleman — pull request #348 by bhollis (2012-04-08 16:34:01+00:00)
Title: Memoize page_by_destination

`page_by_destination` repeatedly calls `Page#destination_path` which then has to apply all the transformation functions. With a lot of pages this turns out to be a noticeable slowdown when rendering each file. Memoizing the mapping of pages by destination path speeds things back up a lot.