问在构造函数定义中使用类别名

EN

class MyClass
{
public: 
    explicit MyClass();

    ~MyClass();
};  

using MyClassAlias = MyClass;

MyClassAlias::MyClassAlias()
{

}

MyClassAlias::~MyClassAlias()
{

}

int main()
{
    MyClassAlias obj;

    return 0;
}   

a.cpp:11:1: error: ISO C++ forbids declaration of ‘MyClassAlias’ with no type [-fpermissive]
   11 | MyClassAlias::MyClassAlias()
      | ^~~~~~~~~~~~
a.cpp:11:1: error: no declaration matches ‘int MyClass::MyClassAlias()’
a.cpp:11:1: note: no functions named ‘int MyClass::MyClassAlias()’
a.cpp:1:7: note: ‘class MyClass’ defined here
    1 | class MyClass
      |       ^~~~~~~