Smarty & module

[elisa_34]

Hi to all
I'm starting to work on smarty and prestashop, i think i nearly understand the module basic architecture.

But, when try to past a function in the lefColumn, with something like this

public function hookleftColumn($params) {
       global $smarty; 
       $smarty->assign (blockfirstmodule::toto());
       $smarty->assign('test', 'my test');
       return $this->display(__FILE__, 'blockfirstmodule.tpl');

}

Well, "my test" is in the right place,
but the output of "toto" take place in two places ! on outside the body and another one in the right column !!!
i just don't get it, please, someone help me

merci