Could this be achieved with decorators?
> On 19 Jan 2016, at 8:31 PM, 森建 <[email protected]> wrote: > > Dear ES discuss subscribers, > > I'm Kenta Moriuchi, > Department of Art and Information Design > Kyushu University in Japan > > I propose `Protected State`. > > In ES2015: > > ```js > // utility > function createProtectedStorage() { > const wm = new WeakMap(); > > return (self, protectedClass) => { > const map = wm.get(self); > > if(protectedClass == null) { > return map || wm.set(self, Object.create(null)).get(self); > } > > const p = new protectedClass(self); > if(map) { > Object.assign(p, map); > } > return wm.set(self, p).get(self); > } > } > > const _ = createProtectedStorage(); > > > class Protected_A { > > constructor(publicThis) { > this.publicThis = publicThis; > } > > getName() { > return `${this.publicThis.name} ${this.lastName}`; > } > } > > class A { > > constructor(name, lastName) { > // protected this > if(new.target === A) _(this, Protected_A); > > // public property > this.name = name; > > // protected property > _(this).lastName = lastName; > } > > callGetName() { > // call protected method > return _(this).getName(); > } > } > > // test > const a = new A("foo", "bar"); > > // "foo bar" > console.log(a.callGetName()); > > // "foo" > console.log(a.name); > > // undefined > console.log(a.lastName); > > > // extends > class Protected_B extends Protected_A { > > constructor(publicThis) { > super(publicThis); > } > > getAge() { > return this.age; > } > > } > > class B extends A { > > constructor(name, lastName, age) { > super(name, lastName); > > // protected this > if(new.target === B) _(this, Protected_B); > > // protected property > _(this).age = age; > } > > callGetAge() { > return _(this).getAge(); > } > > } > > // test > const b = new B("foo", "bar", 18); > > // "foo bar" > console.log(b.callGetName()); > > // 18 > console.log(b.callGetAge()); > ``` > > As Syntax Suger (ES Next): > > ```js > class A { > > protected lastName; > > constructor(name, lastName) { > // public property > this.name = name; > > // protected property > protected.lastName = lastName; > } > > protected getName() { > return `${this.name} ${protected.lastName}`; > } > > callGetName() { > return protected.getName(); > } > > } > > class B extends A { > > protected age; > > constructor(name, lastName, age) { > super(name, lastName); > protected.age = age; > } > > protected getAge() { > return protected.age; > } > > callGetAge() { > return protected.getAge(); > } > > } > ``` > > Please discuss this proposal, thank you. > _______________________________________________ > es-discuss mailing list > [email protected] > https://mail.mozilla.org/listinfo/es-discuss _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
