Regarding the second example, [this resource]( http://exploringjs.com/es6/ch_oop-besides-classes.html#_caveat-objectassign-doesnt-work-well-for-moving-methods) explains why `Object.assign` doesn't work as expected.
I believe the VM should be smarter than that, and let end-developers use any technique for inheritance that they wish. For example,maybe the VM should determine at runtime what the `[[HomeObject]]` is based on what object the method is called on. Seems like that would make `super` much more useful. Doesn't that make more sense? If not, why not? If this were the case, then the first example would work just fine too. */#!/*JoePea On Mon, Jul 18, 2016 at 2:00 PM, /#!/JoePea <[email protected]> wrote: > For example, both of these examples don't work in Chrome: > > ```js > function A() { > console.log('A') > } > A.prototype.constructor = A > A.prototype.hello = function() { > return 'hello' > } > > function B() { > console.log('B') > // super() > A.call(this) > } > B.prototype = Object.create(A.prototype) > B.prototype.constructor = B > B.prototype.hello = function() { > return super.hello() + 'there' > } > > new B > ``` > > and > > ```js > let obj1 = { > hello() { > return 'hello' > }, > sayHello() { > console.log(this.hello()) > } > } > > console.log('Obj1 says hello:') > obj1.sayHello() > > let obj2 = Object.create(obj1) > Object.assign(obj2, { > hello() { > return super.hello() + 'there.' > } > }) > > console.log('Obj2 says hello:') > obj2.sayHello() // Error > ``` > > I was hoping `super` was more flexible than that. > > For example, in the first snippet, why can't `super` simply be a shortcut > for "look up the prototype of the object that the method is called on, then > find the `.constructor` property and call it on `this`"? That seems to be > simple. It could throw an error if `.constructor` is not found, in the case > of ES5-style classes that aren't defined using that pattern that ES6 > classes are syntax sugar for. > > And in the second example, why does `super.hello` not work as expected? > > I believe that these limitations may severely limit my ability to create > the multiple-inheritance tool that I'm imagining over at > https://esdiscuss.org/topic/symbol-for-modifying-property-lookup#content-8 > . > > Any ideas or suggestions? > > > */#!/*JoePea >
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