$this->input->post problem

[eluser]Mitja B.[/eluser]

Code:

foreach($this->input->post => $vrednost)
{
   if (!is_array($this->input->post($kljuc)))
   {
    $this->input->post($kljuc) = htmlspecialchars($this->input->post($kljuc));
   }
}

i want to use htmlspecialchars in all $this->input->post but i get this warning

Parse error: syntax error, unexpected T_DOUBLE_ARROW in C:\HTTPSERVER\wwwroot\bewoop\system\application\controllers\happening.php on line 22