syntax for case ranges

Naveen Chawla naveen.chwl at gmail.com
Mon Feb 3 19:16:26 UTC 2020


Thanks! Although I think it is a value judgement about how much risk is
worth how much reward, and which reward, so I wouldn't classify it as
necessarily a complete set of criteria yet, but it is certainly in the
right direction. And very interesting to me. Thank you.

On Tue, 4 Feb 2020 at 00:40, Mark S. Miller <erights at gmail.com> wrote:

> While correct, each case asked the browser makers to make a risky and
> costly bet. When the risk was low and the payoff high, they've been great
> at doing so. This one does not fall into the viable risk vs reward
> territory.
>
>
> On Mon, Feb 3, 2020 at 7:58 AM kdex <kdex at kdex.de> wrote:
>
>> Yes, there have been numerous backwards-incompatible changes to the
>> language
>> over the years.
>>
>> You can find a list of them in section E of the ECMAScript language
>> standard.
>> IIRC, that list is non-exhaustive.
>>
>> On Monday, February 3, 2020 6:35:12 PM CET Naveen Chawla wrote:
>> > Thank you Claude! I did miss the point.
>> >
>> > Have there ever been "BC" breaks introduced into the language before? If
>> > so, is there a sustainable standard for an "acceptable" one?
>> >
>> > On Mon, 3 Feb 2020 at 22:47, Claude Pache <claude.pache at gmail.com>
>> wrote:
>> > > Try typing `3 < 2 < 1` in the web console of your favourite browser,
>> and
>> > > see the result: it will evaluate to `true`. No, your browser isn’t
>> buggy,
>> > > it is just following blindly the semantics of `<`.
>> > >
>> > > Modifying the meaning of `3 < 2 < 1` in order to make it evaluating
>> to
>> > > `false` is a BC break. Is it acceptable? Dunno.
>> > >
>> > > —Claude
>> > >
>> > > Le 3 févr. 2020 à 15:23, Naveen Chawla <naveen.chwl at gmail.com> a
>> écrit :
>> > >
>> > > Hi!
>> > >
>> > > I didn't understand your reply.
>> > >
>> > > I think currently it would raise an error, because 1 < 2 < 3 is
>> currently
>> > > saying (probably) true < 3.
>> > >
>> > > But a "new" syntax could possibly parse that as a "chain" of
>> comparisons.
>> > >
>> > > Would this be acceptable to introduce into JavaScript (just curious)?
>> > >
>> > > I've probably missed your point entirely, because I saw a short
>> message "3
>> > > < 2 < 1 //true", and I've assumed you meant it in reverse.
>> > >
>> > > On Sat, 1 Feb 2020 at 23:12, Mark S. Miller <erights at gmail.com>
>> wrote:
>> > >> 3 < 2 < 1;  // true
>> > >>
>> > >>
>> > >> On Sat, Feb 1, 2020 at 3:03 AM Naveen Chawla <naveen.chwl at gmail.com>
>> > >>
>> > >> wrote:
>> > >>> Certain languages allow the expression 0<x<5. Does anybody know if
>> this
>> > >>> would be syntactically possible in JavaScript? Of course this would
>> only
>> > >>> apply for "if"/"while" statements.
>> > >>>
>> > >>> On Fri, 31 Jan 2020 at 22:41, Isiah Meadows <
>> contact at isiahmeadows.com>
>> > >>>
>> > >>> wrote:
>> > >>>> Still better to discuss it there - it's highly related to your
>> > >>>> suggestion. And I'm pretty sure an issue already exists related to
>> > >>>> that.
>> > >>>>
>> > >>>> On Fri, Jan 31, 2020 at 09:06 Sultan <thysultan at gmail.com> wrote:
>> > >>>>> The pattern matching proposal does not handles the mentioned case:
>> > >>>>>
>> > >>>>> switch(type) { case 0...5: } being the equivalent of switch(type)
>> {
>> > >>>>> case 0: case 1: case 2: case 3: case 4: case 5: }
>> > >>>>>
>> > >>>>> On Fri, Jan 31, 2020 at 7:36 PM Bruno Macabeus <
>> > >>>>>
>> > >>>>> bruno.macabeus at gmail.com> wrote:
>> > >>>>>> I agree with Oriol.
>> > >>>>>> We already have the proposal pattern matching, that has a very
>> > >>>>>> similar effect.
>> > >>>>>> I think that is better to improve pattern matching proposal in
>> order
>> > >>>>>> to be able to match using ranges (or at least check if it's good
>> to
>> > >>>>>> do)
>> > >>>>>> instead of create a new proposal.
>> > >>>>>>
>> > >>>>>> On Fri, 31 Jan 2020 at 14:08, Oriol _ <
>> oriol-bugzilla at hotmail.com>
>> > >>>>>>
>> > >>>>>> wrote:
>> > >>>>>>> This sounds like
>> https://github.com/tc39/proposal-pattern-matching
>> > >>>>>>>
>> > >>>>>>> El 31/1/20 a les 10:57, Sultan ha escrit:
>> > >>>>>>>
>> > >>>>>>> For example, the following:
>> > >>>>>>>
>> > >>>>>>> switch (value) {
>> > >>>>>>>
>> > >>>>>>>     case 0...9: break
>> > >>>>>>>     case 'a'...'z': break
>> > >>>>>>>
>> > >>>>>>> }
>> > >>>>>>>
>> > >>>>>>>
>> > >>>>>>> _______________________________________________
>> > >>>>>>> es-discuss mailing
>> > >>>>>>> listes-discuss at mozilla.orghttps://
>> mail.mozilla.org/listinfo/es-disc
>> > >>>>>>> uss
>> > >>>>>>>
>> > >>>>>>>
>> > >>>>>>> _______________________________________________
>> > >>>>>>> es-discuss mailing list
>> > >>>>>>> es-discuss at mozilla.org
>> > >>>>>>> https://mail.mozilla.org/listinfo/es-discuss
>> > >>>>>>
>> > >>>>>> _______________________________________________
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>> > >>>>>
>> > >>>>> _______________________________________________
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>> > >>>>> es-discuss at mozilla.org
>> > >>>>> https://mail.mozilla.org/listinfo/es-discuss
>> > >>>>
>> > >>>> --
>> > >>>> -----
>> > >>>>
>> > >>>> Isiah Meadows
>> > >>>> contact at isiahmeadows.com
>> > >>>> www.isiahmeadows.com
>> > >>>> _______________________________________________
>> > >>>> es-discuss mailing list
>> > >>>> es-discuss at mozilla.org
>> > >>>> https://mail.mozilla.org/listinfo/es-discuss
>> > >>>
>> > >>> _______________________________________________
>> > >>> es-discuss mailing list
>> > >>> es-discuss at mozilla.org
>> > >>> https://mail.mozilla.org/listinfo/es-discuss
>> > >>
>> > >> --
>> > >>
>> > >>   Cheers,
>> > >>   --MarkM
>> > >
>> > > _______________________________________________
>> > > es-discuss mailing list
>> > > es-discuss at mozilla.org
>> > > https://mail.mozilla.org/listinfo/es-discuss
>
>
>
> --
>   Cheers,
>   --MarkM
>
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