Hi,

> Is there a way in ocamllex to put back certain characters
> in the buffer. In flex you can do that

It is also possible with Ulex, using Ulexing.rollback.

Even if you don't need the UTF8 features, I suggest you take a
look at Ulex anyway; the approach used (it's a syntax extension)
provides greater flexibility.  Moreover, it also handles latin1
streams fine.

Cheers,
Dario Teixeira