JS里有指针么?

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提到 js 指针,其实我是懵圈儿的,准确来说,应该是没有的,引用倒是满天飞。不过下面的这个例子值得看看。

Are there pointers in javascript?

No, JS doesn’t have pointers.

Objects are passed around by passing a copy of a reference. The programmer cannot access any C-like “value” representing the address of the object.
Within a function one may change the contents of an passed object via that reference, but you cannot modify the reference that the caller had, because your reference is only a copy:

var foo = {'bar': 1};function tryToMungeReference(obj) {  obj = {'bar': 2};  // won't change caller's object}function mungeContents(obj) {  obj.bar = 2;       // changes _contents_ of caller's object}tryToMungeReference(foo);foo.bar === 1;   // true - foo still references original objectmungeContents(foo);foo.bar === 2;  // true - object referenced by foo has been modified

其他参考

JavaScript 的指针是什么?
备注:我还是觉得js里面是没有指针的,除了this指针,更何况,ES6都没有this了。不过js里面绝对有比C里面的指针更刺激的东西,见如下系列。

汤姆大叔的博客-深入理解JavaScript系列

未完待续

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