Re: ECMAScript and chaining

On Thursday, November 22, 2012 at 2:52 PM, Mark S. Miller wrote:

> On Wed, Nov 21, 2012 at 6:31 PM, Rick Waldron <waldron.rick@gmail.com> wrote:
> > On Wed, Nov 21, 2012 at 5:26 PM, Anne van Kesteren <annevk@annevk.nl> wrote:
> > >  
> > > Hi,
> > >  
> > > I was wondering if the plan of TC39 is to start returning the object
> > > on which a method was invoked if that method would otherwise just
> > > return undefined.
> > >  
> >  
> >  
>  
>  
> No, though Rick just placed this on the agenda to discuss at the
> upcoming meeting.
>  
> > > E.g. this seems to be what Object.freeze() and
> > > Object.preventExtensions() do. It's also a somewhat popular API idiom
> > > in jQuery and the like (see also method chaining, fluent interface).
> > >  
> >  
> >  
> >  
> > I'm not sure what you mean by "start"—this is already the prevailing
> > practice.
> >  
>  
>  
> It is most definitely not. Let's discuss more at the upcoming meeting.
I based this statement on the static Object.* API methods that return their target object and Array.prototype methods that return a new array with the results of the operation performed (map filter).  

Rick

>  
>  
> > APIs either return an expected specified value/object, the target
> > object (in the case of static built-ins, eg. Object.freeze(o); // o ) or a
> > new specified object (eg. Array.prototype.{ filter, map } etc.).
> >  
> >  
> > >  
> > >  
> > > (The reason I'm asking is that I just WONTFIXED two bugs asking for
> > > that stating that ECMAScript did not have this pattern either and I
> > > was confronted with the above.
> > >  
> >  
> >  
>  
>  
> Good, thanks.
  
>  
>  
> >  
> >  
> > Links?
> >  
> > >  
> > > I had been looking at Map.set()
> > > myself.)
> > >  
> >  
> >  
> >  
> > The ES6 Map, Set and WeakMap API specifications are still in development and
> > probably shouldn't be used to make decisions like this.
> >  
> > In this particular case there is no rationale documented for these not
> > returning the object they are called from, so it's still open for
> > discussion, ie. Map.prototype.set, Set.prototype.add and
> > WeakMap.prototype.set.
> >  
> > Rick
> >  
> >  
> > >  
> > >  
> > > Cheers,
> > >  
> > >  
> > > --
> > > http://annevankesteren.nl/
> > >  
> >  
> >  
>  
>  
>  
>  
> --
> Cheers,
> --MarkM
>  
>