PHP Reference variable in a class

I am trying to reference a public variable from inside a
class.

class
            Settings{
 public $CompanyName = "MyWebsite"; // company name

            public $PageTitle = "$this->CompanyName - big website"; // E.g. My Big
            Website
}

But
this gives back a parse
error:

Parse error: parse
            error

What
is the correct way of doing this?

class="post-text" itemprop="text">

class="normal">Answer

You can't
set variable with other variable when defining. Use href="http://php.net/manual/en/language.oop5.decon.php"
rel="nofollow">__construct for
it:

class Settings{

            public $CompanyName = "MyWebsite"; // company name
 public $PageTitle; // E.g.
            My Big Website


 public function
            __construct(){
 $this->PageTitle = $this->CompanyName." - big
            website";
 }
}