On Dec 2, 2013, at 7:51 PM, Andrea Giammarchi wrote:

> Reading this: http://esdiscuss.org/topic/november-19-2013-meeting-notes#content-6
> 
> I was wondering if anyone would be so kind to provide a concrete/real-world use case for toMethod() since I am having hard time to imagine a scenario where a super can be so easily invoked, being (AFAIK) multiple inheritance not allowed right now in ES6 specs.

toMethod is a low level primitive that can be used to implement things like Object.mixin in a manner that works correctly with functions that reference super.

> 
> When exactly would a piece of code invoke a super withou knowing which one is it?

Anytime you want to before/after/around wrap a call to the the method that would otherwise be invoked.

Anytime you want to define a "mixin" on an object with a known interface but multiple implementations.

> 
> Wouldn't this lead to potential infinite loop within the super invocation itself if referenced from a subclass that was already using toMethod() within the super() itself?

There is a potential for a super invocation-based unbounded recursion loops, but it doesn't require the use to toMethod to make it occur.  consider

class P { }
class C extends P {
    foo() {
        console.log("f");
        super();
    }
}
P.prototype.foo=C.prototype.foo;
(new C).foo();   //infinite recursion outputting lines of f's

   
If instead you coded:

P.prototype.foo = C.prototype.foo.toMethod(P.prototype);

you would not get the infinite recursion, instead you would get two f's followed by a "method not found" .

Allen
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On Dec 2, 2013, at 7:51 PM, Andrea Giammarchi wrote:

> Reading this: http://esdiscuss.org/topic/november-19-2013-meeting-notes#content-6
> 
> I was wondering if anyone would be so kind to provide a concrete/real-world use case for toMethod() since I am having hard time to imagine a scenario where a super can be so easily invoked, being (AFAIK) multiple inheritance not allowed right now in ES6 specs.

toMethod is a low level primitive that can be used to implement things like Object.mixin in a manner that works correctly with functions that reference super.

> 
> When exactly would a piece of code invoke a super withou knowing which one is it?

Anytime you want to before/after/around wrap a call to the the method that would otherwise be invoked.

Anytime you want to define a "mixin" on an object with a known interface but multiple implementations.

> Wouldn't this lead to potential infinite loop within the super invocation itself if referenced from a subclass that was already using toMethod() within the super() itself?

There is a potential for a super invocation-based unbounded recursion loops, but it doesn't require the use to toMethod to make it occur.  consider

```js
class P { }
class C extends P {
    foo() {
        console.log("f");
        super();
    }
}
P.prototype.foo=C.prototype.foo;
(new C).foo();   //infinite recursion outputting lines of f's
```
   
If instead you coded:

```js
P.prototype.foo = C.prototype.foo.toMethod(P.prototype);
```

you would not get the infinite recursion, instead you would get two f's followed by a "method not found" .