Swiperight direction and docs

I’m using something I found on the web called

<div (swipeleft)="showLeftPage()">
<div (swipright)="showRightPage()">

It works great ! but where the hell are the docs for it ? can’t find anything.
Basically my problem is that - swipeleft & swiperight sliding the page from the same side ( left -> to -> right )
I want the swipeleft to be left -> right, and swiperight will be right -> left

Thanks for the helpers in advanced !

I dumped the event contents and noticed the offset parameter changes. So I wrote this: (I have no idea if this is the right way)

Example:

Code:

<ion-content padding>
  <img (swipe)="swiped($event)"  src="http://via.placeholder.com/350x350?text=swipe left or right" />
<p></p>
Swipe: {{swipeData}}
 swiped(e) {
    switch (e.offsetDirection) {
      case 2: this.swipeData = "right to left"; break;
      case 4: this.swipeData = "left to right"; break;
      default: this.swipeData = "magic"; break;
    }
  }

thank you very much !
Can you tell me why it doesn’t appear in Ionic’s Docs ?
I mean - is it a 3rd party kind of thing ?