How to check for valid Javascript ? Eg - "([{{}}])”

const string = "([{{}}])";

const patternMatch = {
	")": "(",
	"]": "[",
	"}": "{",
};

const validates = (input) => {
	/**
	 * Spread the text to iterate over it
	 * Input = ([]) , Output = ["(","[","]",")"]
	 */
	const array = [...input];
	/**
	 * Get the elements from end
	 */
	let endIndex = array.length - 1;
	let result = true;

	/**
	 * Look closely at patternMatch above,
	 * if we don't find left hand side anymore(keys)
	 * then we have reached the other half(values)
	 */
	array.forEach((item, index) => {
		if (!patternMatch[array[endIndex - index]]) {
			return;
		}
		/**
		 * All this does is get the element
		 * from the last by using index
		 * Otherwise we would have to use pointer
		 * which I'm not a fan of
		 */
		if (item === patternMatch[array[endIndex - index]]) {
			result = true;
		} else {
			result = false;
			return;
		}
	});

	return result;
};

console.log(validates(string));