Arrow notation, etc.

Dylan Thurston dpt@math.harvard.edu
Fri, 12 Oct 2001 20:50:06 +0900


--4Ckj6UjgE2iN1+kY
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Fri, Oct 12, 2001 at 12:39:09PM +0100, Keith Wansbrough wrote:
> Dylan writes:
>=20
> > Incidentally, it seems to me that this is one case where a Lisp-like
> > macro facility might be useful.  With Haskell, it is impossible to
> > play with bindings, while presumably you can do this with good Lisp
> > macro systems.
>=20
> Yes, this is one thing you can do with good macro systems as are found in=
 Lisp and Dylan (the language, not the person!).  See the references in my
>=20
> http://www.cl.cam.ac.uk/~kw217/research/paper-abstracts.html#Wansbrough99=
:Macros
>=20
> Wansbrough, 1999.  Macros and Preprocessing in Haskell
>=20
> especially section 8.

Very good.  Is there a concrete proposal for such macros?  I think the
arrow notation would be a harder test case than any of the existing
syntactic sugar; I'd be curious to see what it looked like.  (And is
there support for adding these macros to Haskell?)

> Hygiene is a key concept here; that variables bound in a macro
> should not clash with other variables in the program (unless this is
> explicitly required).

Off to read some Dylan manuals,
	Dylan

--4Ckj6UjgE2iN1+kY
Content-Type: application/pgp-signature
Content-Disposition: inline

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.0.6 (GNU/Linux)

iD8DBQE7xtjtVeybfhaa3tcRAtNYAJ9uPJeClfndh4OkzUTdyIRpuWcOMACfVQBt
zqOLZVTt/FAREz5gprwW08g=
=mF17
-----END PGP SIGNATURE-----

--4Ckj6UjgE2iN1+kY--