lodash/_baseIsRegExp.js

define(['./isObject'], function(isObject) {

  /** `Object#toString` result references. */
  var regexpTag = '[object RegExp]';

  /** Used for built-in method references. */
  var objectProto = Object.prototype;

  /**
   * Used to resolve the
   * [`toStringTag`](http://ecma-international.org/ecma-262/7.0/#sec-object.prototype.tostring)
   * of values.
   */
  var objectToString = objectProto.toString;

  /**
   * The base implementation of `_.isRegExp` without Node.js optimizations.
   *
   * @private
   * @param {*} value The value to check.
   * @returns {boolean} Returns `true` if `value` is a regexp, else `false`.
   */
  function baseIsRegExp(value) {
    return isObject(value) && objectToString.call(value) == regexpTag;
  }

  return baseIsRegExp;
});