render(): DNode {
		const {
			forId,
			label
		} = this.properties;

		// assign string or object label properites with defaults
		let labelProps: LabelOptions;
		if (typeof label === 'string') {
			labelProps = assign({}, labelDefaults, { content: label });
		}
		else {
			labelProps = assign({}, labelDefaults, label);
		}

		// add label text node to children
		const labelText = v('span', {
			innerHTML: labelProps.content,
			classes: [ this.theme(css.labelText), labelProps.hidden ? baseCss.visuallyHidden : null ]
		});
		if (labelProps.before) {
			this.children.unshift(labelText);
		}
		else {
			this.children.push(labelText);
		}

		return v('label', {
			classes: this.theme(css.root),
			for: forId
		}, this.children);
	}

const props = function(props = {}) {
	return assign({
		controls: 'foo',
		id: 'foo',
		index: 0
	}, props);
};

export const todoSave = function(this: any, event: FormInputEvent) {
	const { properties } = this;
	if (!event.target.value) {
		deleteTodo(properties);
	}
	else {
		updateTodo(assign({}, properties, { label: event.target.value, editing: false }));
	}
};

export const todoSave = function (this: any, event: FormInputEvent) {
	const { state } = this;
	if (!event.target.value) {
		deleteTodo(state);
	}
	else {
		updateTodo(assign(state, { label: event.target.value, editing: false }));
	}
};

		return this.children.filter((child) => child).map(child => {
			// null checks skipped since children are filtered prior to mapping
			assign(child!.properties, {
				onRequestClose: this._assignCallback(child!, 'onRequestClose', this.onRequestClose),
				onRequestOpen: this._assignCallback(child!, 'onRequestOpen', this.onRequestOpen),
				open: includes(openKeys, child!.properties.key),
				theme
			});

			return child;
		});

	function missingFile(path: string) {
		return assign(
			new Error(
				`Error: ENOENT: no such file or directory stat '${path}' errno -2`
			),
			{
				code: 'ENOENT',
				errno: -2,
				syscall: 'stat',
				path
			}
		);
	}