On 01/29/2014 06:00 PM, SiegeLord wrote:
On 01/29/2014 11:44 AM, Niko Matsakis wrote:
On Tue, Jan 28, 2014 at 07:01:44PM -0500, comex wrote:
Actually, Rust already has procedural macros as of recently. I was
wondering whether that could be combined with the proposed new system.
I haven't looked in detail at the procedural macro support that was
recently added, but off hand I think I favor that approach. That is,
I'd rather compile a Rust module, link it dynamically, and run it as
normal, versus defining some subset of Rust that the compiler can
execute. The latter seems like it'll be difficult to define,
implement, and understand. Our experience with effect systems and
purity has not been particularly good, and I think staged compilation
is easier to explain and free from the twin hazards of "this library
function is pure but not marked pure" (when using explicit
declaration) or "this library function is accidentally pure" (when
using inference).
I was under the impression from some time ago that this was going to
be the way CTFE is implemented in Rust. Having tried CTFE in D, I was
not impressed by the nebulous definition of the constant language used
there, it was never clear ahead of time what will work and what won't
(although maybe the problem won't be as big in Rust, as Rust is a
smaller language). Additionally, it was just plain slow (you are
essentially creating a very slow scripting language without JIT).
It seems to me (judging at the size of the loadable procedural macro
commit size) that using staged compilation approach will be easier to
implement and be more powerful at the cost of, perhaps, less
convenient usage.
-SL
I didn't consider procedural macro and wasn't aware that it was in Rust.
I can't find any resources, could someone points me out some documentations?
Cheers,
Pierre Talbot.
_______________________________________________
Rust-dev mailing list
[email protected]
https://mail.mozilla.org/listinfo/rust-dev
