ECMA5.1中Object.seal()和Object.freeze()的区别

1  Object.seal(O)的调用

When the seal function is called, the following steps are taken:
   If Type(O) is not Object throw a TypeError exception.
   For each named own property name P of O,
      Let desc be the result of calling the [[GetOwnProperty]] internal method of O with P.
      If desc.[[Configurable]] is true, set desc.[[Configurable]] to false.
      Call the [[DefineOwnProperty]] internal method of O with P, desc, and true as arguments.
   Set the [[Extensible]] internal property of O to false.
  Return O.

2 Object.freeze(O)的调用

　　If Type(O) is not Object throw a TypeError exception.
　　For each named own property name P of O,
　　　　Let desc be the result of calling the [[GetOwnProperty]] internal method of O with P.
　　　　If IsDataDescriptor(desc) is true, then
　　　　　　If desc.[[Writable]] is true, set desc.[[Writable]] to false.
　　　   If desc.[[Configurable]] is true, set desc.[[Configurable]] to false.
　　　　Call the [[DefineOwnProperty]] internal method of O with P, desc, and true as arguments.
　　　　Set the [[Extensible]] internal property of O to false.
　  Return O.

这两个函数的区别在于伪代码标记部分，这下是终于搞定这两个函数的区别了。