>>>>> "Steve" == Steve Stevenson <steve@cs.clemson.edu> writes:
> 	I need a double-ended queue implementation. The lists
> can get very long, so I would like to use imperative operations to
> change the links.

Since my O'Caml is very approximate, I'll answer with a non-answer:
have you tried a purely functional (but asymptotically efficient)
deque ?  Those don't suffer from the length of the queue.

Chris Okasaki has an interesting set of such purely functional data-structures,
with sample code in SML (and/or Haskell) which should be easy to translate to
O'Caml.  Check out, for example http://www.cs.columbia.edu/~cdo/jfp95/


	Stefan