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  • Generator getter method

Generator getter method

# Mohsen Azimi (10 years ago)

Can we allow generator getter methods?

Here is an example use case:

let rectangle = {
  start: {x: 1, y: 5},
  width: 2,
  height: 3,

  *getCorners() {
    let {x: startX, y: startY} = this.start;
    yield this.start;
    yield {x: startX + this.width, y: startY};
    yield {x: startX + this.width, y: startY + this.height};
    yield {x: startX, y: startY + this.height}
  }
}

for (let corner of rectangle.getCorners()) {
  console.log(corner);
}

I'm proposing to allow get coreners* () { ... (a generator getter method) so the for..of loop can be written like this:

for (let corner of rectangle.corners) {
  console.log(corner);
}

Which seems cleaner

# Kevin Smith (10 years ago)

The existing option is:

let rect = { get corners() { return this._corners(); }, *_corners() { .. }, };

which doesn't seem so bad. Also, a generator getter would introduce a bit of divergence between getter and setter syntax.

# Bergi (10 years ago)

Mohsen Azimi schrieb:

I'm proposing to allow get corners* () { ... (a generator getter method) so the for..of loop can be written like this:

for (let corner of rectangle.corners) {
   console.log(corner);
}

I would avoid that. rectangle.corners !== rectangle.corners could be quite confusing. Creating the generator explicitly is a better idea. And as kevin said, you still can return generators from your getters manually if you really want that.

, Bergi

# Rick Waldron (10 years ago)

On Tue, Nov 10, 2015 at 2:28 PM Mohsen Azimi <me at azimi.me> wrote:

for (let corner of rectangle.getCorners()) { console.log(corner); }


for (let corner of rectangle.corners) {
  console.log(corner);
}

Which seems cleaner

Either could've been called "corners" and then the only difference is the invocation parens.