define(['../internal/baseToString', '../internal/escapeRegExpChar'], function(baseToString, escapeRegExpChar) {

  /**
   * Used to match `RegExp` [syntax characters](http://ecma-international.org/ecma-262/6.0/#sec-patterns)
   * and those outlined by [`EscapeRegExpPattern`](http://ecma-international.org/ecma-262/6.0/#sec-escaperegexppattern).
   */
  var reRegExpChars = /^[:!,]|[\\^$.*+?()[\]{}|\/]|(^[0-9a-fA-Fnrtuvx])|([\n\r\u2028\u2029])/g,
      reHasRegExpChars = RegExp(reRegExpChars.source);

  /**
   * Escapes the `RegExp` special characters "\", "/", "^", "$", ".", "|", "?",
   * "*", "+", "(", ")", "[", "]", "{" and "}" in `string`.
   *
   * @static
   * @memberOf _
   * @category String
   * @param {string} [string=''] The string to escape.
   * @returns {string} Returns the escaped string.
   * @example
   *
   * _.escapeRegExp('[lodash](https://lodash.com/)');
   * // => '\[lodash\]\(https:\/\/lodash\.com\/\)'
   */
  function escapeRegExp(string) {
    string = baseToString(string);
    return (string && reHasRegExpChars.test(string))
      ? string.replace(reRegExpChars, escapeRegExpChar)
      : (string || '(?:)');
  }

  return escapeRegExp;
});