constructor, super, and data members issue

[Jordan Harband]

I'm afraid that still wouldn't solve the problem; the superclass's code is
all 100% completed before the subclass has `this` available.

On Fri, Aug 24, 2018 at 1:52 PM, Ranando King <kingmph at gmail.com> wrote:

> Aaron, congratulations! You just tripped over a new reason for me to
> revive issue #123. The only way to get that to work is to have the default
> values on the prototype. The problem comes because `this` doesn't even have
> a value until the last call to `super()` returns. If a `class` doesn't have
> a base `class` it essentially has Object as a base `class` and `super` is
> implicitly called. So unless the default public field values are on the
> prototype, there's literally no way to have them initialized before the
> base classes are initialized.
>
> On Fri, Aug 24, 2018 at 3:15 PM Aaron Gray <aaronngray.lists at gmail.com>
> wrote:
>
>> I am having an issue with order semantics regarding https://github.com/
>> tc39/proposal-class-fields with derived classes defining or overriding
>> data member values that are used in the base class constructor for
>> initialization of properties of the class.
>>
>> This means the Super Class / Base Class'es constructor does not yet have
>> access to the default field values of the derived class it is initiating.
>>
>>     class Base {
>>         constructor() {
>>              ....
>>              .. idAttribute ..
>>              ....
>>         }
>>         idAttribute = 'id';
>>     }
>>    class Derived extends Base {
>>         constructor() {
>>              super();
>>              ....
>>         }
>>         idAttribute = '_id';
>>    }
>>
>> All would mean having a separate initialize() function, but even this
>> solution is flawed when there is a third level in the hierarchy. And as
>> super() is required it means there seems to be no way round this issue. The
>> only way I can see is some form of override keyword ?
>>
>>
>> Has anyone got any solutions to this issue or work arounds ?
>> --
>> Aaron Gray
>>
>> Independent Open Source Software Engineer, Computer Language Researcher,
>> Information Theorist, and amateur computer scientist.
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>>
>
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