Additional Set.prototype methods

Erik Arvidsson erik.arvidsson at gmail.com
Wed Jan 8 16:56:58 PST 2014


I always envisioned that we would create a full fledged iter module and
then we would define these functions once and for all.
On Jan 8, 2014 6:32 PM, "Calvin Metcalf" <calvin.metcalf at gmail.com> wrote:

> specific to set (as opposed to ones that work with array) would be the
> mathematical set operations like union, symmetrical difference (think xor),
> compliment, and intersection.
>
>
> On Fri, Jan 3, 2014 at 12:52 PM, Tab Atkins Jr. <jackalmage at gmail.com>wrote:
>
>> On Tue, Dec 31, 2013 at 11:36 AM, David Bruant <bruant.d at gmail.com>
>> wrote:
>> > Hi,
>> >
>> > I've been playing with Sets recently and believe that the following
>> > additions would make them more useful by default:
>> > * Set.prototype.map
>> > * Set.prototype.filter
>> > * Set.prototype.toJSON = function(){
>> >     return [...this];
>> > };
>> >
>> > The 2 first are to easily create sets from existing sets very much like
>> what
>> > we already have with arrays. I haven't had a use for a .reduce yet, but
>> > maybe that would make sense too?
>> > The toJSON is just to provide a good default. Obviously anyone
>> disatisfied
>> > with it can shadow it on specific instances. But this serialization
>> makes
>> > more sense by default than the one you get now (own properties of the
>> set
>> > object... which have none in common usages?)
>>
>> I agree with adding more of the array primitives to sets - sets are
>> just an "weakly ordered" version of arrays, so basically all of them
>> make sense.
>>
>> map() is the only troublesome one, because it can produce a smaller
>> set, if you return the same value from multiple iterations.  This
>> isn't necessarily bad, but it's surprising.
>>
>> ~TJ
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>>
>
>
>
> --
> -Calvin W. Metcalf
>
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