Getter/Setter as function

Question

Is it possible to create property getter/setter as a function?

Standard getter/setter work like following:

class Test {
  something: any;

  get prop() {
    return something;
  }
  set prop(value) {
    something = value;
  }
}

let instance = new Test();
instance.prop = 'Foo';
console.log(instance.prop); // = Foo

I would need following:

let instance = new Test();
instance.prop('Bar') = 'Foo'; // access setter as a function of prop
console.log(instance.prop('Bar')); // = Foo

Yes, I know it's unorthodox usage and yes, I know that I could implement this functionality bit differently. I'm just interested if this is possible in JS/TS/ES6.

Update

This is the closest I got:

class Test {
  something: any;

  prop(area /* my custom symbol type */) {
    const obj: any = {};
    Object.defineProperty(obj, 'value', {
      // get child object of my complex object
      get: () => this.something[area];
      // replace part of my complex object
      set: (value) => {
        this.something = {...this.something, [area]: value}
      }
    });
  }
}

let instance = new Test();
instance.prop('Bar').value = 'Foo';
console.log(instance.prop('Bar').value); // = Foo

So in short, I'd like to get rid of value suffix if possible.

Since syntactically you *cannot* assign to a function call… no. — deceze, Sep 29 '17 at 14:24
Possible duplicate of [ES6 getter/setter with arrow function](https://stackoverflow.com/questions/33827519/es6-getter-setter-with-arrow-function) — Daniel Mizerski, Sep 29 '17 at 14:27
Looks confusing... at least it has to be `instance.prop('Foo')` as a setter, `instance.prop()` - getter — FieryCat, Sep 29 '17 at 14:28
Another way of doing this, similar to what FieryCat is saying, would be `instance.prop('Bar', 'Foo')` to set and `instance.prop('Bar')` to get. — Mike Cluck, Sep 29 '17 at 14:29
@deceze: What I want is a getter function that takes an argument to say pre-filter or reduce the result. Of course this would be possible with getting everything first and filtering later. I was just wondering whether it could be possible to hide it behind a getter/setter. — Miroslav Jonas, Sep 29 '17 at 14:47
@MikeC, as mentioned my question was not how to do it differently, but rather is it possible to solve it this way. — Miroslav Jonas, Sep 29 '17 at 15:02
@MiroslavJonas I know but as deceze said, what you want is not possible. I was merely presenting something that *is* possible. — Mike Cluck, Sep 29 '17 at 15:12

score 0 · Answer 1 · answered Sep 29 '17 at 15:08

0

As @deceze mentioned in the first comment, it is not possible to assign to function call, so solution in the update is as best as it gets.

answered Sep 29 '17 at 15:08

Miroslav Jonas

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Getter/Setter as function

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