是否允许delete this;delete-statement是将在该类实例上执行的最后一个语句?当然,我确信this-pointer所代表的对象是newly-created.
我在考虑这样的事情:
void SomeModule::doStuff()
{
// in the controller, "this" object of SomeModule is the "current module"
// now, if I want to switch over to a new Module, eg:
controller->setWorkingModule(new OtherModule());
// since the new "OtherModule" object will take the lead,
// I want to get rid of this "SomeModule" object:
delete this;
}
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我可以这样做吗?
c++ memory-management new-operator self-destruction delete-operator
请考虑以下代码:
#include <iostream>
struct foo
{
// (a):
void bar() { std::cout << "gman was here" << std::endl; }
// (b):
void baz() { x = 5; }
int x;
};
int main()
{
foo* f = 0;
f->bar(); // (a)
f->baz(); // (b)
}
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我们期望(b)崩溃,因为x空指针没有相应的成员.在实践中,(a)不会崩溃,因为this从不使用指针.
因为(b)取消引用this指针((*this).x = 5;),并且this为null,程序进入未定义的行为,因为取消引用null总是被称为未定义的行为.
会(a)导致未定义的行为吗?如果两个函数(和x)都是静态的呢?
c++ standards-compliance null-pointer undefined-behavior language-lawyer