这什么时候应该>使用？ [英] When should this-> be used?

问题描述

我想知道是否应该同时使用this->：

I was wondering if this-> should be used both:

void SomeClass::someFunc(int powder)
{
     this->powder = powder;
}

//and
void SomeClass::someFunc(bool enabled)
{
     this->isEnabled = enabled;
}

我想知道后者是否有必要或isEnabled =

I'm wondering if the latter is necessary to be proper or if isEnabled = enabled would suffice.

谢谢

推荐答案

this->

。

请考虑以下问题：

#include <iostream>

template <class T>
class Foo
{
   public:
      Foo() {}
   protected:
      void testing() { std::cout << ":D" << std::endl; }
};

template <class T>
class Bar : public Foo<T>
{
   public:
      void subtest() { testing(); }
};

int main()
{
   Bar<int> bar;
   bar.subtest();
}

这将失败，因为调用testing（）取决于模板参数。要说您的意思是函数，您将必须执行 this-> testing（）; 或 Foo< T> :: testing（）;。

This will fail since calling testing() is dependent on a template parameter. To say that you mean the function you will have to do this->testing(); or Foo<T>::testing();

错误消息：

temp.cpp: In member function ‘void Bar<T>::subtest()’:
temp.cpp:16:32: error: there are no arguments to ‘testing’ that depend on a template parameter, so a declaration of ‘testing’ must be available [-fpermissive]
temp.cpp:16:32: note: (if you use ‘-fpermissive’, G++ will accept your code, but allowing the use of an undeclared name is deprecated)

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