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Re: [Scheme-reports] multiple values module

5 hours ago, John Cowan wrote:
> Eli Barzilay scripsit:
> > And that's very unfortunate.  Things like (list (values 1 2) 3)
> > are nonsensical when you talk about their *meaning*, because
> > values are not *specified* as things that are reified as first
> > class values.  Either way (specifying such a reification or making
> > it behave like multiple values) is far better than the
> > neither-here-nor-there mess.
> I agree that it's nonsensical.  I emphatically don't agree that the job
> of this standard is to make all nonsense illegal.

How can you agree or not agree with something I didn't say?

> R6RS is a standard that tries.  ECMAScript 5th edition and HTML5 try
> even harder to, prescribing the exact behavior of every
> implementation on every possible string of input characters.

(This is going from nonsensical to ridiculous.)

> R5RS, and following it R7RS, prescribes certain things and leaves
> others up to the implementation.

(And this is trivially true about any standard.)

> > > Or you can use a unique type, or even a non-unique type. [...]
> > > Chibi's use cases just aren't anything like Racket's.
> >
> > How is Racket related to anything I've said?
> Its use cases are about as remote from Chibi's as could be. [...]

Again, unrelated.

> > In this implementation, (car (values)) becomes a dangerous
> > implementation-exposing value.
> As far as the standard is concerned, evaluating (car (values))
> licenses your implementation to make demons fly out of your nose.

Same here.

> I am not being flippant: see
> http://www.catb.org/jargon/html/N/nasal-demons.html .

I know the jargon thankyouverymuch.  I also know the language that
inspired it -- and I certainly hope that its not used as an excuse to
make Scheme similarly crappy.

> > > Ultimately, if you want R6RS, you know where to find it.
> >
> > Why the inferiority complex?
> You've missed my point.  I mentioned R6RS as an instance of the kind
> of restrictive standard I explained above.

I wasn't talking about it, or about any standard.

> > This is the kind of childish reply that makes r7rs look like a
> > childish response to r6rs.  Coming from the chairman of wg2 makes
> > this kind of response worse.
> Why?  Do you imagine that the WG2 charter has anything to do with
> R6RS, other than to avoid _gratuitous_ incompatibility with a
> suitably chosen subset of it?

No, I wasn't thinking about WG2, its charter, R6RS, or any kind of

> > And once you've fixated into that complex, you just continue with
> > it not looking left or right.  Here's a list of words that were
> > not used in my post:
> >
> >   * R5RS R6RS R7RS R[0-9]*RS Standard Conform.*
> Once you've talked about what implementations should or should not
> do, you are in the realm of conformance, even if only conformance to
> a standard in your head.

I didn't talk about what implementations should or shouldn't do;
you're arguing with someone who lives in your head.

What I talked about is: either multiple values are reified as first
class values or not, both sides can be defined well enough.  Reifying
them in such a bad way as chibi does is **I*M*O** extremely bad, and
should not be used as any kind of an example.  A third option is to
specify neither, and resort to the same lame nasal demons point from
that other language.  Choosing this approach is something that
**I*M*O** is as fine of an idea as chibi's "implementation" of
multiple values.  A similar decision would be to not require a garbage
collector, or tail calls, or a number of other features, each reducing
the practicality of the result (and increasing the number of
implementations that can call themselves scheme).  If r6rs does
specify some semantics that are better than nasal demons (I didn't
even bother checking), then taking that back would be **I*M*O** an
obvious step back -- but that's not my problem.  r7rs is in any case
going for something less useful, intentionally.  But this whole
paragraph is full of stuff that I didn't talk about, and I mention it
all just because you brought it up.  My guess is that you're likely to
reply only to it, and repeat yet again how chibi is allowed to do so.

          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
                    http://barzilay.org/                   Maze is Life!

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