12 Oct
2008
12 Oct
'08
5:08 p.m.
J. Garrett Morris wrote:
Hello everyone,
As part of a project to formalize the theory of overlapping instances, I'm looking for examples of overlapping and incoherent instances and their usage. One such example would be the old version of the Monad Transformer Library, which used overlapping instances together with MonadTrans. Any other examples or suggestions would be greatly appreciated!
I use overlapping instances extensively with my (unpublished) work on heterogeneous and extensible unification. In particular, the portion based on Swierstra's _Data Types a la Carte_[1]. I'm sure other folks have been using DTalC for interesting projects as well. [1] http://wadler.blogspot.com/2008/02/data-types-la-carte.html -- Live well, ~wren