Fwd: [Haskell-cafe] What's the deal with Clean?

I had to implement a ring buffer, and I wanted the code using it to be written in Haskell. I ended up implementing the buffer in C, and wrapping it in FFI from Haskell because implementing a destructive array in Haskell is kind of unwieldy to someone of my experience level. In Clean, it looks like the uniqueness typing allows for destructive updates in a very controlled manner.

The ST monad provides this functionality. The never-instantiated-in-a-visible-way state parameter of the ST monad provides the "uniqueness" required for doing destructive updates in a pure way.