private static IllegalArgumentException newMissingParametersException( String value ) {
		return new IllegalArgumentException( "missing parameters in function '" + value + "'" );
	}
For use in LazyValue to get value for given key from UIManager and report error
if not found. If key is prefixed by '?', then no error is reported.
flatlaf-core/src/main/java/com/formdev/flatlaf/UIDefaultsLoader.java