function getIdentifiers($as_string = true) {
		$ident = array_keys($this->identifiers);
		return (($as_string) ? implode('', $ident) : $ident);
	}
function getIdentifiers($as_string = true) {
		$ident = array_keys($this->identifiers);
		return (($as_string) ? implode('', $ident) : $ident);
	}
Returns identifier characters as string/array
@param bool $as_string Should the result be a string or an array?
@return string|array
@see setIdentifiers()