public function validateParam($param, $err = null)
    {
        return $this->validate($this->request->param($param), $err);
    }
public function validateParam($param, $err = null)
    {
        return $this->validate($this->request->param($param), $err);
    }
public function validateParam ( $ param , $ err = null ) { return $ this -> validate ( $ this -> request -> param ( $ param ) , $ err ) ; }
Start a validator chain for the specified parameter

@param string $param     The name of the parameter to validate
@param string $err       The custom exception message to throw
@return Validator
Start a validator chain for the specified parameter