Domain classes use temporary created objects in method calls which makes the comparison of a tobject to "this" in a domain class method by the strict equality operator impossible. The introduction of the %equals% method solves this problem and gives the developer a reliable way to test if two tobjects represent the same topic.
Examples
[%$kurt = Tobject::get("si:kurt");
$mary = Tobject::get("si:mary");
// Another tobject
if ($kurt->equals($mary)) ...
// A topic reference
if ($kurt->equals("si:mary")) ...
// A system id
if ($kurt->equals(779)) ...%]