dev-haskell/categories
The Categories package authored by Edward Kmett
USE Flags
optimize
* This flag is undocumented *
doc
Global: Adds extra documentation (API, Javadoc, etc)
hscolour
* This flag is undocumented *
hoogle
* This flag is undocumented *
profile
Global: Adds support for software performance analysis (will likely vary from ebuild to ebuild)