src/vs/editor/standalone/common/monarch/monarchLexer.ts/MonarchStackElement/getStackElementId
class MonarchStackElement:	public static getStackElementId(element: MonarchStackElement | null): string {
		let result = '';
		while (element !== null) {
			if (result.length > 0) {
				result += '|';
			}
			result += element.state;
			element = element.parent;
		}
		return result;
	}