Properly speaking, this is not a “Wolf” function at all. PHP uses a special variable, $this->, which always points to the “current object”. But what is the “current object”? In Wolf, the meaning of $this-> depends on where you use it. Here is it how works:

• in the Layout, $this-> points at currently displaying page, whatever it is.
• in the Body of page, $this-> points at that page only.
• in a Page-part, $this-> points at the page to which that part belongs — even if it is “inherited” by child pages with the “true” condition as in:
  • <?php $this->content('sidebar', true); ?>
  • For example, if the “sidebar” of “Homepage” uses $this->, and that sidebar is inherited by child pages, then $this-> still refers to the homepage.
• in a Snippet, $this-> will behave as outlined above, depending on whether you call the snippet in your layout, in the body of a page, or in a page-part.

That can be summarized in a table as follows: