src/vs/workbench/services/themes/common/textMateScopeMatcher.ts/newTokenizer
function newTokenizer(input: string): { next: () => string | null } {
	let regex = /([LR]:|[\w\.:][\w\.:\-]*|[\,\|\-\(\)])/g;
	let match = regex.exec(input);
	return {
		next: () => {
			if (!match) {
				return null;
			}
			const res = match[0];
			match = regex.exec(input);
			return res;
		}
	};
}