[TYPES] seeking papers with good examples of the use of GADTs

[Derek Dreyer]

I would highly recommend Fritz Henglein's ICFP'08 paper, "Generic
Discrimination: Sorting and Partitioning Unshared Data in Linear
Time":

http://portal.acm.org/ft_gateway.cfm?id=1411220&type=pdf&coll=GUIDE&dl=GUIDE&CFID=30629082&CFTOKEN=48962619

It provides a very elegant use of GADTs for expressing distributive
sorting algorithms in a compact, composable way.  Also, the motivation
(sorting) is as basic as it gets, and the paper has a good mixture of
theory and Haskell code to chew on.  There are probably some elements
of the paper that your students will have trouble with, but they are
not essential ones.

Derek

On Fri, Apr 10, 2009 at 11:05 PM, Norman Ramsey <nr at eecs.harvard.edu> wrote:
> [ The Types Forum, http://lists.seas.upenn.edu/mailman/listinfo/types-list ]
>
>
> I have a class of beginning functional programmers; we're approaching
> end of term, and I'd like them to learn about GADTs.  One of my goals
> in the class is to give students practice learning by reading papers,
> so I am asking for recommendations of papers that have good examples
> of GADTs in action.   Papers I've used in the past have included
>
>  Pottier and Gauthier 2005: Polymorphic Typed Defunctionalization and
>  Concretization, in Higher-Order and Symbolic Computation
>
>  Pottier and Régis-Gianas 2006: Towards Efficient, Typed LR Parsers,
>  in Electr. Notes Theor. Comput. Sci
>
> and
>
>  Peyton Jones et al. 2006: Simple unification-based type inference
>  for GADTs, in the 11th ACM SIGPLAN International Conference on
>  Functional Programming.
>
> Unfortunately the first two rely on concepts in which my students have
> little background (LR parsing and defunctionalization respectively),
> and the the third, while it opens with a nice example, is primarily
> about the (now obsolete) type-inference algorithm, rather than about
> how to use GADTs.
>
> I am hoping some of you may have suggestions about other papers that
> would be good tutorials in the use of GADTs.
>
>
> Norman
>
>
>