[racket-dev] [racket] Question about round

This is my opinion, too.

Robby

On Fri, Sep 30, 2011 at 11:20 AM, Matthew Flatt <mflatt at cs.utah.edu> wrote:
> I think this is a good change for the next language, but not for `#lang
> racket'.
>
> As confusing as the current `integer?' may be, I think its definition
> is deeply wired into our code, tests, and documentation. I may guess
> wrong, but my best estimate of the hassle for this change is that it's
> too much trouble for too little payoff, and we could spend our energy
> on more interesting things.
>
> At Fri, 30 Sep 2011 11:59:25 -0400, Vincent St-Amour wrote:
>> On a more general note, do we really need inexact integers?
>>
>> The behavior of `integer?' is confusing, and I don't see especially
>> compelling reasons to keep it this way. The subject comes up every
>> couple of months on the mailing list, so we should do something about it.
>>
>> Here's a proposal:
>> `integer?' becomes the same as `exact-integer?' (which is kept for
>> backwards compatibility).
>> `positive-integer?' and `nonnegative-integer?' are added as
>> equivalents to their `exact' counterparts.
>> `inexact-integer?' is added, to cover for the use case of checking is
>> an inexact number has been rounded.
>>
>> I volunteer to implement this if we agree that this is the right
>> thing.
>>
>> Vincent
>>
>>
>>
>> At Fri, 30 Sep 2011 07:16:22 -0600,
>> Doug Williams wrote:
>> >
>> > Another such annoyance is than (min 1 +inf.0) => 1.0 - because if any
>> > argument is inexact, the result is inexact. I don't think this makes sense
>> > in the case of infinities. Infinities are very useful as initial values for
>> > things that are being minimized or maximized, but there is always the need
>> > for inexact->exact to protect against the (unexpected) coercion.
>> >
>> > This is all from the original R5RS and continued in R6RS - but, we aren't
>> > that language.
>> >
>> > Could we get an exception to the coercions in the case of +/-inf.0? Or an
>> > alternative min/max that don't do it?
>> >
>> > On Fri, Sep 30, 2011 at 6:53 AM, Matthias Felleisen
>> <matthias at ccs.neu.edu>wrote:
>> >
>> > >
>> > > exact-round is preferred.
>> > >
>> > >
>> > >
>> > > On Sep 30, 2011, at 8:51 AM, Eli Barzilay wrote:
>> > >
>> > > > Yesterday, Ryan Culpepper wrote:
>> > > >> The pragmatic answer is you generally have to write
>> > > >>
>> > > >>   (inexact->exact (round x))
>> > > >>
>> > > >> which is annoying, but no one has yet bothered to add a standard
>> > > >> library function for this, as far as I know.
>> > > >
>> > > > [From the annoyed side, especially since that thing tends to come in
>> > > > bunches which can make some quick code look much heavier than it is:]
>> > > >
>> > > > Maybe it's time to add something for that?  `eround'?  (But even
>> > > > `exact-round' would be better than the above.)
>> > > >
>> > > > --
>> > > >          ((lambda (x) (x x)) (lambda (x) (x x)))          Eli Barzilay:
>> > > >                    http://barzilay.org/                   Maze is Life!
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