1 files changed, 13 insertions, 0 deletions
diff --git a/node_modules/es6-weak-map/is-weak-map.js b/node_modules/es6-weak-map/is-weak-map.js
new file mode 100644
index 000000000..10bb2a156
--- /dev/null
+++ b/node_modules/es6-weak-map/is-weak-map.js
@@ -0,0 +1,13 @@
+'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;
+};