What's the good reason that object-initializer methods can't be constructors though? I mean, I get that "that's what spec says", but what's the actual good reason?
The problem here would be solved with a dynamic super. I feel that ES6 diverges from ES5 in backwards-incompatible ways. Some people say ES6 classes are "syntax sugar" over the ES5 constructor pattern classes, but, *not really*, since they aren't compatible in the same places. ES6 classes and object-initializer methods are not backwards-incompatible in a bad way because they cannot be treated the same as we are used to in ES5 (f.e. copying methods with underscore's `_.extend()` doesn't work because of static HomeObjects), and that is backwards-incompatible with previous concepts, ideas, and methodologies that we love JavaScript for. Some old code might do something like ```js _.extend(SomeClass.prototype, OtherClass.prototype) ``` where `SomeClass` and `OtherClass` are ES5 constructor-pattern classes. If the classes are updated to be ES6 classes, then that code may fail because of the static `HomeObject` properties, and that is backwards-incompatible with the paradigms and patterns of ES5. **A dynamic super would remedy this problem.** For now, I am contemplating using a custom and dynamic `Object.prototype.super` getter in all apps where my code runs so that my ES6 classes remain as flexible as in ES5. The overhead associated with a custom `Object.prototype.super` would only be due to the fact that it is not possible for us to hook into the native property lookup algorithm, otherwise the overhead of finding a HomeObject would be completely negligible because the native property lookup algorithm already finds the HomeObject where a property or method is located and therefore it would cost next to nothing to use the found HomeObject on a method call by passing HomeObject as an argument in the native side of the JS engine. */#!/*JoePea On Wed, Jul 27, 2016 at 7:58 AM, Allen Wirfs-Brock <[email protected]> wrote: > The most common case is the “methods” are designed to be used as > constructors. This has always be recognized for built-in methods in the > ECMAScript specification which says: "Built-in function objects that are > not identified [in this specification] as constructors do not implement the > [[Construct]] internal method unless otherwise specified in the description > of a particular function.”. When “concise methods” where add as part of > Object Initializers and Class Definitinos this default was applied to them. > > You can still define constructible properties for Object Initializers, > just not by using concise method syntax: > > ```js > let classes = { > Cat: function() {}, > Dog: function() {}, > Bird: class {} > }; > > let [c, d, b] = [new classes.Cat, new classes.Dog, new classes.Bird]; > ``` > > > > > >
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