Jon Harrop wrote:

On Monday 28 January 2008 14:23:01 you wrote:

Jon Harrop wrote:

There are also many features that I would like to steal from other
languages:

. The IDisposable interface from .NET and F#'s "use" bindings.

Is there a reason that Gc.finalise doesn't work?


Absolutely: Gc.finalise is only probabilistic whereas IDisposable is 
deterministic. IDisposable guarantees deallocation of resources by a certain 
point. (This is why you should never use Gc.finalise alone to manage the 
collection of external resources!)

So you write a "use" binding:

  let read_first_line file =
    use ch = open_in file in
    input_line ch

and it gets translated into:

  let read_first_line file =
    let ch = open_in file in
    try input_line ch finally
    ch#dispose

What happens when I write:
    let broken file =
       use ch = open_in file in
       (fun () -> input_line ch)
? Or some other tricky way to let ch escape the scope?

Monads strike me as being a better way to do this, but again, we're talking about deep changes to Ocaml. The alternative- wait until the object is garbage collected, depends upon the form of the garbage collector.

Brian