[Still staying in this thread although bad match to subject line, as I'd like to continue on the discussion of open vs closed classes]
Brendan Eich wrote: > > On Jul 22, 2009, at 3:10 AM, Christian Plesner Hansen wrote: > > >> The current class proposal, > >> > >> http://wiki.ecmascript.org/doku.php?id=strawman:classes > >> > >> has zero inheritance. > > > > I was under the impression that the plan was to develop some form of > > inheritance model too. The strawman says that there is no > inheritance > > to keep the design simple. Are you sure you're not > throwing the baby > > out with the bathwater here? > > Nothing is thrown out by starting simple and then considering our > options. I agree a lot with Alex about wanting the ability to create non- frozen classes with the new class mechanism (with respect for not having the whole picture as you in the committee have). Once the new class mechanism was deployed I was hoping to be able to use it for any class-oriented problem, and not having to fall back on old-style prototypes/constructors for certain kinds of classes. With the current (small) feature list of classes I guess it's hard to provide any hard arguments against keeping old-style constructors for open classes, and it *is* elegant to keep the purpose of existing language mechanisms. Though, to me it looks like there is a risk that this design will not fit so well when later expanding the feature list with f ex inheritance or class introspection, and that will leave open classes in the back-water and developers facing questions like: - Ah, you want to use the new non-clunky inheritance mechanism that doesn't force you to actually set up the inheritance through a constructor call to the superclass? Sorry, only available in frozen classes. - Or, you want the new inheritance mechanism that chains constructor calls at instance creation? Only available in frozen classes. - Or, you want to introspect the class to see what members instances will get, without creating and introspecting an actual instance? Only in frozen classes. Of course I am only speculating about potential future additions here, but it is easy to fear that the old-style constructors will have a hard time keeping up with a class mechanism that actually has a class declaration to build features upon. Best regards Mike _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
