[Haskell-cafe] Type-level programming [The container problem]

Aaron Denney wrote:

On 2008-09-27, Andrew Coppin wrote:

...

Ah - so the "Prolog programs as type signatures" thing is *his* fault?! ;-)

No, he merely takes advantage of it.

Heh. OK. ;-) By the way... I've seen a lot of type-level programs that allow you to express (and therefore verify) some pretty extreme properties of your code. In other words, you can make the compiler do more checking than it normally would. But the actual compiled code (assuming it does indeed compile) works exactly the same way as before. Is there any way to use type-level programming to actually alter the behaviour of the program in a useful/interesting way?