了解JavaScript、Mozilla中的内存管理

我不熟悉

JavaScript

，并试图了解与使用此Mozilla引用的对象相关的内存管理：

我在举一个例子，但在理解参考资料时遇到了问题

var o = { 
  a: {
    b:2
  }
}; 
// 2 objects are created. One is referenced by the other as one of its property.
// The other is referenced by virtue of being assigned to the 'o' variable.
// Obviously, none can be garbage-collected

   var o2 = o; // the 'o2' variable is the second thing that 
                // has a reference to the object
    o = 1;      // now, the object that was originally in 'o' has a unique reference
                // embodied by the 'o2' variable

    var oa = o2.a; // reference to 'a' property of the object.
                   // This object has now 2 references: one as a property, 
                   // the other as the 'oa' variable

    o2 = "yo"; // The object that was originally in 'o' has now zero
               // references to it. It can be garbage-collected.
               // However what was its 'a' property is still referenced by 
               // the 'oa' variable, so it cannot be free'd

    oa = null; // what was the 'a' property of the object originally in o 
               // has zero references to it. It can be garbage collected.

我被一些术语弄糊涂了，比如这个对象，一个被另一个引用，创建了两个对象-是为了什么o'&'a'？，它引用了对象-哪个对象？

有人能用实际的对象名来重新表述上面的评论吗

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它可能被认为是一个调羹问题，但如果不值得问这个问题，请告诉我。我会删除它

这是一个有点蹩脚的解释。我给你一个粗略的版本

var o = { 
  a: {
    b:2
  }
}; 
// 2 objects are created. One (the value of the property named "a")
// is referenced by the other (the value of the variable named "o")
// as its property.
// The other (the value of the variable named "o")
// is referenced by virtue of being assigned to the 'o' variable.
// Obviously (maybe to the author...), none can be garbage-collected

var o2 = o; // the 'o2' variable now also
            // has a reference to the object (the value of the variable "o")

o = 1;      // "o" now refers to something else and "o2" is the only variable
            // referring to the original "o" object.

var oa = o2.a; // reference to the 'a' property of the "o2" object.

o2 = "yo"; // The object that was originally in 'o' has now zero
           // references to it, but
           // the object's 'a' property is still referenced by 
           // the 'oa' variable, so the "o2" object cannot yet
           // be GC'ed.

oa = null; // The object now has zero references to it, so it can be
           // garbage collected.

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对象没有名称；这就是重点。存在引用对象的变量（或对象属性），或者没有。JavaScript具有对象的文字符号。这些对象可以将其他对象作为其特性。