Re: features of PCRE-OCaml

[Alain Frisch <frisch@clipper.ens.fr>]

On Sat, 9 Dec 2000, John Max Skaller wrote:

> > Have a look at wlex:
> >  This reduces the number of states and transitions in the automaton,
> 
> 	No, it has no effect on the number of states (rows of the
> DFA matrix). It reduces the number of columns.

Yes it does: the extra classification layer may consume more than one
character in the lexbuf. When you parse UTF-8 with ocamllex, you have
"waiting" states in the automaton corresponding to multibyte encoded code
points.

> > wlex is distributed as a patch to ocamllex.
> 
> 	That's always a worry. Am I confused: does it change the
> Ocaml source tree in place, or just copy bits of it and patch them?
> Why is Findlib required? (Thats a patch too, isn't it?)

It would have been much easier for me not to distribute wlex as a patch,
but this is incompatible with the license.

The Makefile doesn't touch the source tree in place; it just makes a copy
of the lex/ directory and works on it. Findlib, which is not a patch, is
required only to install the runtime support library of wlex; you can
of course use this library directly.


-- 
  Alain Frisch