On Sep 14, 2014, at 7:47 PM, Domenic Denicola wrote: > I want to give a +1 to Allen. The syntax really is > what-you-see-is-what-you-get, which is a great virtue. The C++-derived > initializer is cute and tempting, but not nearly as powerful or easy to grok. > > That said, I feel weakly that requiring the correct `this = new > super(...)`and/or `this = Object.create(new^.prototype)` invocation is a high > price to pay for every derived class ever. In particular, "basic constructor > functions" (ES5 "classes") that don't wish to use the superclass constructor > don't need `this = Object.create(new^.prototype)`, so making ES6 classes > require that is strange. It feels like protypal inheritance has "broken" once > you start using ES6 classes, and it requires you to fix it by manually doing > something that was previously implicit. > > I think I'd most be in favor of a third option that implicitly adds `this = > Object.create(new^.prototype)` if no `this`-assignment is present. That way, > the superclass constructor is never implicitly called, which is kind of what > you would expect. But if you do no `this =` assignment, things don't totally > break: you still get your prototype and a valid `this`, but you don't inherit > the allocation or initialization logic from the superclass.
Thanks, that's a plausible third alternative to the two variations we already have. I'll take a look at creating a gist for that alternative. Since there has been a lot of talk about verboseness of `this=` I want to compare several alternatives for a derived class that wants to do it's own allocation: (this is derived from the last example in https://gist.github.com/allenwb/291035fbf910eab8e9a6 ): If `this=` assignment is not allowed then any locally allocating method has to look something like this: ```js constructor(a) { let newO = new^.specialAllocationMethod(); //or Object.create(new^), etc. newO.a = a; return newO; } ``` with `this`` assignment it looks like: ```js constructor(a) { this = new^.specialAllocationMethod(); //or Object.create(new^), etc. this.a = a; } ``` Which is more verbose? Allen
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