1 files changed, 12 insertions, 0 deletions
diff --git a/node_modules/es6-set/is-set.js b/node_modules/es6-set/is-set.js
new file mode 100644
index 000000000..6b491ddee
--- /dev/null
+++ b/node_modules/es6-set/is-set.js
@@ -0,0 +1,12 @@
+'use strict';
+
+var toString          = Object.prototype.toString
+  , toStringTagSymbol = require('es6-symbol').toStringTag
+
+  , id = '[object Set]'
+  , Global = (typeof Set === 'undefined') ? null : Set;
+
+module.exports = function (x) {
+	return (x && ((Global && ((x instanceof Global) || (x === Global.prototype))) ||
+			(toString.call(x) === id) || (x[toStringTagSymbol] === 'Set'))) || false;
+};