Callable objects protocol

[Ranando King]

That's the kind of thing I was shooting for with static lexical scope
variables. There's 2 problems with it given the way things are going
though. Take a look.

```js
function foo() {
  static a=1,
         b=2,
         c=3;
}
```
By the way I'm thinking, this would create 3 static variables within foo
that are only initialized once and retain whatever value is set on them
across invocations. Basically, the object `foo` carries around a closure
containing those values. Problem is, this is private to foo. That conflicts
with class-fields and it's sigil-means-private model.

Ignoring that, public static variables can also be done (but it'd be the
first ever introduction of `public` in ES.
```js
function foo() {
  static public a=1,
                b=2,
                c=3;
}
```
This would make `foo.a`, `foo.b`, & `foo.c` accessible as public properties
of `foo`.

Think this needs to be a proposal?


On Wed, Dec 5, 2018 at 1:39 AM Isiah Meadows <isiahmeadows at gmail.com> wrote:

> Personally, I'd prefer something else: a means of a function object
> literal that's still callable, but I can tack other properties to it
> easily. Something like this, maybe:
>
> ```js
> {
> (...args) { ... },
> }
> ```
>
> In this, the `this` value is set to the callee itself, not the given
> `this` value.
>
> Not married to the syntax, but I want the functionality.
> On Wed, Dec 5, 2018 at 01:34 Andrea Giammarchi <
> andrea.giammarchi at gmail.com> wrote:
>
>> > the apply hook needs objects anyway.
>>
>> I meant functions
>>
>> On Wed, Dec 5, 2018 at 1:33 PM Andrea Giammarchi <
>> andrea.giammarchi at gmail.com> wrote:
>>
>>> I've actually replied to the op, I didn't mean to answer you directly,
>>> but the only reason I wrote that is because I could, no other reasons.
>>>
>>> However, people unaware of the handleEvent pattern for event listeners
>>> often hope to be able to pass objects as listeners, ignoring the fact they
>>> can do that already (but they need a handleEvent method, own or inherited,
>>> in that object).
>>>
>>> There is at least another use case I can't remember now, but I do
>>> remember doing the Proxy dance before ending up realizing that the apply
>>> hook needs objects anyway.
>>>
>>> But yeah, I don't think it's a must have, specially because we can have
>>> something similar already, as shown in my example.
>>>
>>>
>>> On Wed, Dec 5, 2018 at 1:25 PM Ranando King <kingmph at gmail.com> wrote:
>>>
>>>> Maybe I asked it wrong.
>>>>
>>>> How is making an ordinary object callable at all useful for anything
>>>> that can't already be easily handled via objects and functions? (looking
>>>> for use cases here)
>>>> How does this make coding easier to do and understand? (for the AST
>>>> parser and for the human)
>>>>
>>>> On Tue, Dec 4, 2018 at 11:54 PM Andrea Giammarchi <
>>>> andrea.giammarchi at gmail.com> wrote:
>>>>
>>>>> How about this:
>>>>>
>>>>> ```js
>>>>>
>>>>> // the poly
>>>>> if (!Symbol.callable)
>>>>>   Symbol.callable = Symbol('callable');
>>>>>
>>>>> // the setup
>>>>> class Callable extends Function {
>>>>>   constructor(object) {
>>>>>     super('return arguments.callee[Symbol.callable](...arguments)');
>>>>>     //            sloppy mode FTW!
>>>>>     Object.setPrototypeOf(this, object);
>>>>>   }
>>>>> }
>>>>>
>>>>>
>>>>> // the example
>>>>> const obj = new Callable({
>>>>>   [Symbol.callable](value) {
>>>>>     return value + this.value;
>>>>>   },
>>>>>   value: 123
>>>>> });
>>>>>
>>>>> obj(7); // 130
>>>>>
>>>>>
>>>>> ```
>>>>>
>>>>> On Wed, Dec 5, 2018 at 12:02 AM Sultan <thysultan at gmail.com> wrote:
>>>>>
>>>>>> Something along the lines of Symbol.iterator protocol for defining
>>>>>> callback objects i.e: Symbol.callable:
>>>>>>
>>>>>> const obj = {
>>>>>>     [Symbol.callable]: function (...args) { return
>>>>>> this[Symbol.for('value')] },
>>>>>>     [Symbol.for(''value')]: 'value',
>>>>>> }
>>>>>>
>>>>>> assert(obj() === 'value')
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>
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