git.r.bdr.sh - rbdr/dotfiles/blob

   1 'use strict';
   2
   3 var getPrototypeOf = Object.getPrototypeOf, prototype = Object.prototype
   4   , toString = prototype.toString
   5
   6   , id = Object().toString();
   7
   8 module.exports = function (value) {
   9         var proto, constructor;
  10         if (!value || (typeof value !== 'object') || (toString.call(value) !== id)) {
  11                 return false;
  12         }
  13         proto = getPrototypeOf(value);
  14         if (proto === null) {
  15                 constructor = value.constructor;
  16                 if (typeof constructor !== 'function') return true;
  17                 return (constructor.prototype !== value);
  18         }
  19         return (proto === prototype) || (getPrototypeOf(proto) === null);
  20 };