On Wednesday 24 October 2001 12:32, Simon Peyton-Jones wrote:
> The elimination of "stupid" existential wrapper constructors
> is discussed in a bit more detail in the paper Mark and I wrote
> recently:
>
> First class modules for Haskell
http://research.microsoft.com/~simonpj/papers/first-c
| artificial restriction. I think extending the system with
| some form of
| subtyping between records would be important for a usable
| system. Your
| paper suggested that you are planning to do this. Any
| thoughts on current
| ideas in this direction?
Yes, we should really say some
Simon Peyton-Jones writes:
:
| A key design choice in our system is to use *nominal* not *structural*
| typing. The structural choice makes perfect sense, but it leads to
| complications we don't have (as well as benefits). So we don't have
| structural subtyping, and it would not be easy