C++ 编译器错误 C4430：缺少类型说明符 - 假定为 int
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Compiler error C4430: missing type specifier - int assumed
提问by user3571201
I have this error:
我有这个错误：
"error C4430: missing type specifier - int assumed. Note: C++ does not support default-int"
“错误 C4430：缺少类型说明符 - 假定为 int。注意：C++ 不支持 default-int”
with this code example :
使用此代码示例：
//A.h
#include "B.h"
class A{
B* b;
..
};
//B.h
#include "A.h"
class B{
A* a; // error error C4430: missing type specifier - int assumed.
};
回答by songyuanyao
This is a circular dependencyissue. For declaring a pointer to some class, the definition of the class is not needed; i.e. the type doesn't have to be a complete type.
So you don't need to include A.hin B.h, forward declarationis enough. Such as:
这是一个循环依赖问题。为了声明一个指向某个类的指针，不需要类的定义；即类型不必是完整类型。所以你不需要包含A.hin B.h，前向声明就足够了。如：
//B.h
class A; // change the include of A.h to forward declaration
class B {
A* a;
};
