function is_error( $emask = null ) {
		$e = $this->get_error_level();
		if( $emask === null ){
			return (bool) $e;
		}	
		else {
			return (bool) ( $e & $emask );
		}
	}
function is_error( $emask = null ) {
		$e = $this->get_error_level();
		if( $emask === null ){
			return (bool) $e;
		}	
		else {
			return (bool) ( $e & $emask );
		}
	}
function is_error ( $ emask = null ) { $ e = $ this -> get_error_level ( ) ; if ( $ emask === null ) { return ( bool ) $ e ; } else { return ( bool ) ( $ e & $ emask ) ; } }
Test whether this object is in a state of error
@param int php error level constant
@return bool
Test whether this object is in a state of error