Function replace

packages/utils/renderer/marked.js:1248–1258

(regex, opt)

	}

	function replace(regex, opt) {
		regex = regex.source;
		opt = opt || '';
		return function self(name, val) {
			if (!name) return new RegExp(regex, opt);
			val = val.source || val;
			val = val.replace(/(^|[^\[])\^/g, '$1');
			regex = regex.replace(name, val);
			return self;
		};
	}

	function noop() {}
	noop.exec = noop;