> On Apr 24, 2017, at 12:34 PM, Bradley Meck <[email protected]> wrote:
>
> To an extent, yes. You can use hoisting of function declarations and circular
> dependencies to create a "gateway". During circular dependencies, you have a
> time where function declarations are available but evaluation has not
> occured. During that time you can setup your private state. Then, immediately
> on evaluation, remove your gateway.
>
> ```
> // file: ./secrets
>
> // import all friendly modules (note: all dependencies of these modules could
> access GATEWAY)
> import './a'
> GATEWAY = void 0;
>
>
> // storage for shared secrets
> let SECRET;
Really clever!
Doesn’t this need to be a `var` declaration. Otherwise, the initial test of
SECRET will be in its TDZ the first time GATEWAY is called.
> // gateway
> function GATEWAY() {
> if (!SECRET) SECRET = {};
> return SECRET;
> }
> export {GATEWAY};
> ```
>
> ```
> // file: ./a
> import {GATEWAY} from './secrets';
> if (typeof GATEWAY !== 'function') {
> throw Error('import secrets *first*.');
> }
> const SECRET = GATEWAY();
> ```
>
> With Realms (https://github.com/tc39/proposal-realms
> <https://github.com/tc39/proposal-realms>) you may be able to use the
> completion value of Module Evaluation to also achieve a way to share private
> state in a more sane way. VM implementations allow this in some ways as well
> :
> https://github.com/v8/v8/blob/a71c338d9e24e55b47125108a0fce754076751d0/include/v8.h#L1109
>
> <https://github.com/v8/v8/blob/a71c338d9e24e55b47125108a0fce754076751d0/include/v8.h#L1109>
>
_______________________________________________
es-discuss mailing list
[email protected]
https://mail.mozilla.org/listinfo/es-discuss
