lodash/_cloneRegExp.js

define([], function() {

  /** Used to match `RegExp` flags from their coerced string values. */
  var reFlags = /\w*$/;

  /**
   * Creates a clone of `regexp`.
   *
   * @private
   * @param {Object} regexp The regexp to clone.
   * @returns {Object} Returns the cloned regexp.
   */
  function cloneRegExp(regexp) {
    var Ctor = regexp.constructor,
        result = new Ctor(regexp.source, reFlags.exec(regexp));

    result.lastIndex = regexp.lastIndex;
    return result;
  }

  return cloneRegExp;
});