[Haskell-cafe] A Question of Restriction

Brian Troutwine goofyheadedpunk at gmail.com
Mon Jul 27 19:06:32 EDT 2009

Hello Wouter.

I've had a go at the paper linked and perused other references found
with Google. Unfortunately, such sophisticated use of the type system
is pretty far out of my normal problem domain and I can't see how to
apply the techniques presented to my motivating example. Would you be
so kind as to elaborate?

Thank you,

On Mon, Jul 27, 2009 at 2:37 AM, Wouter Swierstra<wss at cs.nott.ac.uk> wrote:
> Hi Brian,
> If I understand you correctly, you've run into the "Expression Problem".
> Phil Wadler posed the problem in a widely-cited e-mail, formulating it much
> more clearly than I ever could:
>  http://homepages.inf.ed.ac.uk/wadler/papers/expression/expression.txt
> There are lots of ways to tackle this problem in Haskell - just google
> "Expression Problem Haskell". My (completely biased) personal favourite is:
>  http://www.cse.chalmers.se/~wouter/Publications/DataTypesALaCarte.pdf
> Hope this helps,
>  Wouter

More information about the Haskell-Cafe mailing list