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

   1 'use strict';
   2
   3 module.exports = function () {
   4         var map;
   5         if (typeof WeakMap !== 'function') return false;
   6         map = new WeakMap();
   7         if (typeof map.set !== 'function') return false;
   8         if (map.set({}, 1) !== map) return false;
   9         if (typeof map.clear !== 'function') return false;
  10         if (typeof map.delete !== 'function') return false;
  11         if (typeof map.has !== 'function') return false;
  12
  13         return true;
  14 };