node/tools/eslint/node_modules/es6-weak-map/is-weak-map.js
Michaël Zasso 2d441493a4 tools: update eslint to v1.10.3
PR-URL: https://github.com/nodejs/io.js/pull/2286
Reviewed-By: Roman Reiss <me@silverwind.io>
2016-01-13 23:15:39 +01:00

13 lines
379 B
JavaScript

'use strict';
var toStringTagSymbol = require('es6-symbol').toStringTag
, toString = Object.prototype.toString
, id = '[object WeakMap]'
, Global = (typeof WeakMap === 'undefined') ? null : WeakMap;
module.exports = function (x) {
return (x && ((Global && (x instanceof Global)) ||
(toString.call(x) === id) || (x[toStringTagSymbol] === 'WeakMap'))) ||
false;
};