@Override
protected boolean createSubstitutes(
List<ParseTreeNode> substitutes, Map<String, ParseTreeNode> bindings) {
List<Directive> subsets = new ArrayList<Directive>();
for (String subsetName : directives) {
subsets.add(new Directive(FilePosition.UNKNOWN, subsetName));
}
substitutes.add(new DirectivePrologue(FilePosition.UNKNOWN, subsets));
return true;
}