Gregory Crosswhite wrote:

Something that I have been wondering for a while is: why are there *still* two monad transformer libraries with seemingly identical functionality, especially given that they have conflicting namespaces? It creates stupid problems like the one that Erik encountered and had to work around.

I recognize that this situation most likely came about via historical accident rather than by intention, but why does it continue to be true?

The intention is to migrate to transformers, which has a slightly better design and separates out the functional dependencies into a separate package (monads-fd), thus allowing use of the type families variant (monads-tf) instead. This has been discussed to some extent on the libraries list and a workable strategy involving making a new mtl 2.0 that re-exports transformers has been suggested. However the migration from extralibs to the Haskell Platform put the brakes on further progress for a bit. Now that this migration is essentially complete I have been intending to revive the proposal but haven't got round to it yet. Please do jump in and do so yourself if you feel motivated! Cheers, Ganesh =============================================================================== Please access the attached hyperlink for an important electronic communications disclaimer: http://www.credit-suisse.com/legal/en/disclaimer_email_ib.html ===============================================================================