List<IFileElementType> () { return Arrays.stream(FileTypeManager.getInstance().getRegisteredFileTypes()) .filter(type -> type instanceof LanguageFileType) .map(type -> ((LanguageFileType)type).getLanguage()) .map(LanguageParserDefinitions.INSTANCE::forLanguage) .filter(Objects::nonNull) .map(ParserDefinition::getFileNodeType) .collect(Collectors.toList()); }