[racket-dev] else clauses: possible change to match?

Can you point to some examples?

Note that you can still use else, as long as you don't refer to it as a
variable.

On Friday, May 3, 2013, J. Ian Johnson wrote:

> I've used else as a catch-all binding in match. Yes, it's not the best
> practice, but I think since I've done it, other people must have done it
> too. This could annoy them.
> -Ian
> ----- Original Message -----
> From: "Robby Findler" <robby at eecs.northwestern.edu <javascript:;>>
> To: "Sam Tobin-Hochstadt" <samth at ccs.neu.edu <javascript:;>>
> Cc: dev at racket-lang.org <javascript:;>
> Sent: Friday, May 3, 2013 11:04:27 AM GMT -05:00 US/Canada Eastern
> Subject: Re: [racket-dev] else clauses: possible change to match?
>
>
> Given that we don't yet even have a prototype of racket2, I'm going to
> guess that "near" isn't all that near. IMO, there are other big things that
> we should be focused on going first (notably the package system).
>
>
> Just to check again: Is no one concerned with the backwards
> incompatibility issue?
>
>
>
> Robby
>
> On Friday, May 3, 2013, Sam Tobin-Hochstadt wrote:
>
>
> Right, I agree with this. My question is basically: are we going to,
> in the reasonably near future, be encouraging people to program in a
> `#lang racket2` where `cond` works differently, in which case it
> doesn't seem worth it to change `match`. Otherwise, I'll do this now.
>
> Sam
>
> On Fri, May 3, 2013 at 10:42 AM, Robby Findler
> < robby at eecs.northwestern.edu <javascript:;> > wrote:
> > Cond's else cannot change. I agree that that's what I would change if I
> > could have it back to do it over, but we cannot.
> >
> > That's the way to perhaps be thinking about racket2, tho.
> >
> > Robby
> >
> >
> > On Friday, May 3, 2013, Sam Tobin-Hochstadt wrote:
> >>
> >> On Fri, May 3, 2013 at 10:22 AM, Robby Findler
> >> < robby at eecs.northwestern.edu <javascript:;> > wrote:
> >> >
> >> > For this kind of thing, my preference would be to change match than to
> >> > issue
> >> > a warning. I don't like warnings that are basically admitting
> weaknesses
> >> > in
> >> > the language design.... Of course, changing a core thing like that may
> >> > be
> >> > more trouble than it is worth, due to backwards compatibility
> concerns,
> >> > which is why I think it is worth raising here to see what others
> think.
> >>
> >> I'm happy to make this change to `match`, except that I've heard
> >> Matthew say that he would have used a keyword for `else` in `cond` if
> >> he had it to do over again, and I wouldn't want to change one way, and
> >> then change back.
> >>
> >> Sam
>
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