在其他类变量中引用类变量

I have the following in a class.

class My_Class {
    $x = 'happy';
    $y = array( 'iam' => $this->x);
    //getting a 500 error with that.
    function __construct() {
        // scripts, etc
    }
}

I get an unexpected $this (T_VARIABLE). Any thoughts?

You can't use $this when defining the instance variables. Try this alternative:

class My_Class {
    var $x = 'happy';
    var $y = array();

    function __construct() {
        $this->y['iam'] = $this->x;
    }
}

You cannot put a variable in the class definition. Constants work, but anything else (concatenation, etc) will throw an error.