E.13: Never throw while being the direct owner of an object
E.13: 直接拥有一个对象所有权时永远不要抛出异常
Reason(原因)
That would be a leak.
那样做会发生泄露。
Example（示例）
代码语言：javascript复制void leak(int x) // don't: may leak
{
auto p = new int{7};
if (x < 0) throw Get_me_out_of_here{}; // may leak *p
// ...
delete p; // we may never get here
}One way of avoiding such problems is to use resource handles consistently:
避免这种问题的一种方法是始终如一地使用资源句柄。
代码语言：javascript复制void no_leak(int x)
{
auto p = make_unique<int>(7);
if (x < 0) throw Get_me_out_of_here{}; // will delete *p if necessary
// ...
// no need for delete p
}Another solution (often better) would be to use a local variable to eliminate explicit use of pointers:
另外一个解决方案（通常更好）是用局部变量来避免使用指针。
代码语言：javascript复制void no_leak_simplified(int x)
{
vector<int> v(7);
// ...
}Note（注意）
If you have local "things" that requires cleanup, but is not represented by an object with a destructor, such cleanup must also be done before a throw. Sometimes, finally() can make such unsystematic cleanup a bit more manageable.
如果局部的“某物”需要清除，但却没有实现为一个具有析构函数的对象，这些清理操作也必须在抛出异常之前进行。有时，finally函数可以让这种非系统化的清理动作稍微容易管理一些。
原文链接https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#e13-never-throw-while-being-the-direct-owner-of-an-object
