Additional cascading Map/Set/WeakMap methods?

Brandon Benvie brandon at brandonbenvie.com
Sun Jan 13 18:53:43 PST 2013


In that case, it would be really nice for .set to return the value so these
work:

    return map.has(key) ? map.get(key) : map.set(key, val);

and

    return map.get(key) || map.set(key, val);


On Sunday, January 13, 2013, Mark S. Miller wrote:

> My reversal was posted at
> <https://mail.mozilla.org/pipermail/es-discuss/2012-December/026932.html>.
> Thanks there to Jussi Kalliokoski for also clearing up this issue.
>
> On Sun, Jan 13, 2013 at 6:45 PM, Mark S. Miller <erights at google.com<javascript:;>>
> wrote:
> > Since then, due to issues pointed out here on es-discuss, I withdrew
> > my consensus from this decision.
> >
> > See also <
> https://mail.mozilla.org/pipermail/es-discuss/2012-December/026971.html>
> > where Andreas states the issue more clearly than I did.
> >
> >
> > On Sun, Jan 13, 2013 at 4:44 PM, Allen Wirfs-Brock
> > <allen at wirfs-brock.com <javascript:;>> wrote:
> >> At the last TC39 meeting, it was agreed tothat the set/add methods
> would return the collection that to which something is being added.
> >>
> >> This supports code patterns like:
> >>
> >> someMap.set(key1,value1).set(key2,value3);
> >>
> >> In making this change to the spec. I noticed several other methods that
> could reasonably be used in this same pattern. For example:
> >>
> >> someMap.clear().set(aKey, aValue);
> >>
> >> someSet.delete(oldMember).add(newMember);
> >>
> >> Are there any objections to making the clear and delete methods of
> Map/WeakMap/Set also return the collection, just like set/add?
> >>
> >> Allen
> >>
> >>
> >>
> >> _______________________________________________
> >> es-discuss mailing list
> >> es-discuss at mozilla.org <javascript:;>
> >> https://mail.mozilla.org/listinfo/es-discuss
> >
> >
> >
> > --
> >     Cheers,
> >     --MarkM
>
>
>
> --
>     Cheers,
>     --MarkM
> _______________________________________________
> es-discuss mailing list
> es-discuss at mozilla.org <javascript:;>
> https://mail.mozilla.org/listinfo/es-discuss
>
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