--- /dev/null
+'use strict';
+var $ = require('../internals/export');
+var IS_PURE = require('../internals/is-pure');
+var anObject = require('../internals/an-object');
+var getSetIterator = require('../internals/get-set-iterator');
+var iterate = require('../internals/iterate');
+
+// `Set.prototype.join` method
+// https://github.com/tc39/proposal-collection-methods
+$({ target: 'Set', proto: true, real: true, forced: IS_PURE }, {
+ join: function join(separator) {
+ var set = anObject(this);
+ var iterator = getSetIterator(set);
+ var sep = separator === undefined ? ',' : String(separator);
+ var result = [];
+ iterate(iterator, result.push, { that: result, IS_ITERATOR: true });
+ return result.join(sep);
+ }
+});