Quick question - scope of a Page/Component

Hi folks,

Imagine you have two pages, each has it’s own folder and files, like this:

  • page-one
    — one.ts
    — one.html
    — one.scss
  • page-two
    — two.ts
    — two.html
    — two.scss

Let’s say one.ts has a property, like this:

export class SelectiveSyncPage {

    public types: Array<any> = [];


Why is it that I can, from two.html, reference the property types in one.ts ? Shouldn’t it be out of its scope?

I saw this in ionic3-components starter.
app.html has this on line 62
<img class="user-avatar round" [src]="chosenPicture || placeholder" onerror="this.src='assets/img/avatar/girl-avatar.png'"

But app.component.ts has no mention of that property. Another page does. Is this broken? Or it works?