Restricted Data Types

[Ben Rudiak-Gould]

Jim Apple wrote:
> Have we considered Restricted Data Types?
> 
> http://www.cs.chalmers.se/~rjmh/Papers/restricted-datatypes.ps

I'd never seen this paper before. This would be a really nice extension to 
have. The dictionary wrangling looks nasty, but I think it would be easy to 
implement it in jhc. John, how about coding us up a prototype? :-)

-- Ben