Set的forEach有问题吧

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#1 Created at ... [Delete] [Delete and Lock User]

var set = new Set([1, 2, 3]);
set.forEach(function (element, type ,self) {
    console.log(element);
    console.log(type);
    console.log(self);
})

结果是： 1 1 Set {1, 2, 3} 2 2 Set {1, 2, 3} 3 3 Set {1, 2, 3}

如果是两个参数：

var set = new Set([1, 2, 3]);
set.forEach(function (element ,self) {
    console.log(element);
    console.log(self);
})

结果是： 1 1 2 2 3 3

说明Set的forEach也应该是3个参数，并且第三个参数是其本身

#2 Created at ... [Delete] [Delete and Lock User]

你说得对，set前两个参数是完全一样的：