XHP Attribute Selection

When working with XHP, use the ->: operator to retrieve an XHP class attribute value.

The operator can also be used on arbitrary expressions that resolve to an XHP object (e.g. $a ?? $b)->:).

use namespace Facebook\XHP\Core as x;

final xhp class user_info extends x\element {
  attribute int userid @required;
  attribute string name = "";

  protected async function renderAsync(): Awaitable<x\node> {
    return
      <x:frag>User with id {$this->:userid} has name {$this->:name}</x:frag>;
  }
}