Re: [Caml-list] ANN: patterns v0.4

[Richard Jones <rich@annexia.org>]

On Tue, Jun 17, 2008 at 10:58:35PM +0100, Jeremy Yallop wrote:
> Nathaniel Gray wrote:
> >On Tue, Jun 17, 2008 at 4:20 AM, Jeremy Yallop <jeremy.yallop@ed.ac.uk> 
> >wrote:
> >>I'm pleased to announce a new release of `patterns', an OCaml
> >>framework for writing extensions to pattern matching using Camlp4.
> >
> >Ooh, very interesting!  Have you looked at "active patterns" in F#?
> >They look really useful and I've been wanting to code them up in
> >camlp4 for a while now but haven't had the time.  It sounds like your
> >framework could make that much easier.
> 
> Yes, one of the reason for writing the framework was to be able to 
> implement F#-like active patterns.  I think it should be reasonably 
> straightforward to do -- in fact, I'd expect design considerations to 
> take up more time than actual implementation work (although I say that 
> from the perspective of being already familiar with the "patterns" 
> framework, of course).  If I remember rightly, there's a note at the end 
> of the ICFP07 active patterns paper about using polymorphic variants to 
> add active patterns in OCaml, which seems like it might be a good 
> starting point.

Can someone summarise active patterns for us?  The MSDN site
containing the paper is down at the moment.

> You might also be interested in the "views" feature of Martin Jambon's 
> "Micmatch", which is along the same lines as active patterns:
> 
>      http://martin.jambon.free.fr/micmatch-manual.html#htoc10

Is anyone working on upgrading micmatch to 3.10?

Rich.

-- 
Richard Jones
Red Hat