domenic at domenicdenicola.com (2013-07-15T22:42:25.839Z)
On Jul 12, 2013, at 9:01 AM, Mark Miller wrote:
> And I find that equally bizarre and unpleasant.
ToInteger is an internal operation. Algorithms that call it can explicitly check for infinities if it is important to them. However, a quick scan of its current uses shows that passing through infinities is exactly want is needed in most cases.
`Number.toInteger` is a language level function and it is certainly reasonable to explicitly discuss what it should return for infinities (and for that matter NaN and -0). So what do you think it should do for those cases?
Also, the current `Math.isInteger` spec. is just plan bogus:
3. If integer is not equal to number, return false.
What (in the spec.) does "not equal" mean? I must have been asleep at the keyboard or maybe it's strawman language that slipped through into the spec. without adequate review...
On Jul 12, 2013, at 9:01 AM, Mark Miller wrote: > > > > On Fri, Jul 12, 2013 at 8:58 AM, Luke Hoban <lukeh at microsoft.com> wrote: > >From: Allen Wirfs-Brock [mailto:allen at wirfs-brock.com] > > > > >> > >> 2) Is it intentional that Number.toInteger(Infinity) returns true? > >Huh? How's that? > > > >Number.toInteger is specified as the single step: > > > > 1 Return ToInteger(number) > > > >and step 4 of the abstract operation ToInteger(number): > > > > 4 If number is +0, -0, +∞, or -∞, return number. > > > > Sorry, I meant 'isInteger'. Per your quoted section, toInteger(Infinity) is Infinity, so isInteger(Infinity) is true. > > And I find that equally bizarre and unpleasant. ToInteger is an internal operation. Algorithms that call it can explicitly check for infinities if it is important to them. However, a quick scan of its current uses shows that passing through infinities is exactly want is needed in most cases. Number.toInteger is a language level function and it is certainly reasonable to explicitly discuss what it should return for infinities (and for that matter NaN and -0). So what do you think it should do for those cases? Also, the current Math.isInteger spec. is just plan bogus: 3. If integer is not equal to number, return false. What (in the spec.) does "not equal" mean? I must have been asleep at the keyboard or maybe it's strawman language that slipped through into the spec. without adequate review... Allen -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mail.mozilla.org/pipermail/es-discuss/attachments/20130712/e149c2b5/attachment.html>