Overloading the tilde operator?

[Dave Benjamin]

Neil Cerutti wrote:
> There's been only one (or two?) languages in history that
> attempted to provide programmers with the ability to implement
> new infix operators, including defining precedence level and
> associativity (I can't think of the name right now).

You're probably thinking of SML or Haskell. OCaml also allows you to 
define new infix operators, but the associativities are fixed (and 
determined by what punctuation you use).