Allen Wirfs-Brock schrieb:

On Dec 16, 2014, at 1:18 PM, Bergi wrote:
...

I've read <https://esdiscuss.org/topic/referencing-super> and it seems that needing to 
call `super.describe()`/`super.render()`/`super.say()` is intended behaviour. I'm fine with 
that, as explicit is better than implicit and "finding the method with the same 
*name*" (or something like that) is overly complicated and maybe even ambiguous.

Yes, this is a fairly recent change to the ES6 draft specification. People who 
write public commentary and tutorials about ES6 need to keep up with evolving 
spec changes.

Sure they do, but I didn't even know that there was an earlier revision where this had once worked. Thanks for the clarification!

However, it seems that we need to communicate better that `super()` calls only work 
in constructors, and other functions that inherit from functions 
(<http://people.mozilla.org/~jorendorff/es6-draft.html#sec-getsuperconstructor>).
Rev 29 made `new super` and `new super ( )` early errors in non-constructor 
concise methods.

Ah, <http://people.mozilla.org/~jorendorff/es6-draft.html#sec-object-initializer-static-semantics-early-errors> and <http://people.mozilla.org/~jorendorff/es6-draft.html#sec-class-definitions-static-semantics-early-errors>. I had not seen that.

It might be nice if there was a note about these in the Static Semantics for the `super` keyword productions (http://people.mozilla.org/~jorendorff/es6-draft.html#sec-super-keyword-static-semantics-early-errors)

> It doesn't do the same thing for `super( )` calls that appears to be an editorial mistake that I will correct in Rev 30.

Thanks!

Should an exception been thrown if the `func` returned by 
`GetSuperConstructor()` is `%FunctionPrototype%`?

It it [[Prototype]] was set ot %FunctionPrototype% from a different realm?

I think the early error described above is a better solution as it address the 
syntactic context of the usage rather than actual runtime value.

Yes indeed. This will fit the needs of the majority who *declare* their methods in object literals or classes much better than a runtime exception (which was just the first idea that had come to my mind). And we probably don't need to care about those who manually assign functions and call `.toMethod()` etc.

However, I wonder whether the same thing should be done in non-concise method assignments, i.e. `PropertyDefinition : PropertyName : AssignmentExpression`. As the `PropertyDefinitionEvaluation` handles the "IsFunctionDefinition of AssignmentExpression" case specially, I think the static semantics for it should do so as well (and forbid `super` calls in them).

 Bergi
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