diagrams/diagrams-core — pull request #24 by byorgey (2012-08-31 21:20:04+00:00)
Title: Fix for juxtaposeDefault to correctly handle empty envelopes

This fixes one part of https://github.com/diagrams/diagrams-lib/issues/37 -- in particular, it means that `mempty` is now an identity element.

I haven't yet investigated the other problem in that issue, but plan to look at it soon -- I'll push a fix to this same branch once I do.