js escape regex pattern characters

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// Hint: it is most optimal way to escape patterns represent as strings.

// Escapes regular expression pattern special characters in the indicated string.
//
const escapePattern = (pattern) => {
	let result = '';
  	for (let i = 0; i < pattern.length; ++i) {
    	const entry = pattern[i];
      	switch (entry) {
            case '^':
            case '$':
            case '*':
            case '+':
            case '?':
            case '.':
            case '{':
            case '}':
            case '(':
            case ')':
            case '[':
            case ']':
            case '=':
            case ':':
            case '!':
            case '|':
            case '/':
            case '\\':
                result += '\\' + entry;
                break;

            default:
                result += entry;
                break;
        }
    }
  	return result;
};


// Usage example:

const pattern = escapePattern('.*');

console.log(pattern);  // '\.\*'