Hola, no estoy seguro de por qué recibo este error. Básicamente lo entiendo en estas tres líneas:

PLS-00363: expression 'p_temp_foo.editable.modified_by' cannot be used as an assignment target
PLS-00363: expression 'p_temp_foo.editable.date' cannot be used as an assignment target
PLS-00363: expression 'p_temp_foo.editable.modified_by' cannot be used as an assignment target

procedimiento

 PROCEDURE run_temp_procedure (p_temp_foo IN part_bean, p_member_number IN NUMBER)
 IS
 t_temp_foo part_bean;
  now   DATE;
  BEGIN
  now := SYSDATE;

             p_temp_foo.editable:= t_temp_foo.editable;
        p_temp_foo.editable.date := SYSDATE;
        p_temp_foo.editable.modified_by := p_member_number;


  END run_temp_procedure ;