directives.append(this);
            }
        }

        void collectFilesInto(Collection<IncludeFileEdge> files, Set<File> seen) {
            if (includeDirectives != null && seen.add(file)) {
                files.addAll(edges);
                for (FileVisitResult include : included) {
                    include.collectFilesInto(files, seen);
                }
            }
        }

        @Override