C ++成员初始化VS继承的构造方法初始化

Question

I know that one way to initiate members of a class is to write the following:

class base {
 int id;
 public:
 base(int id): id(id){}
};

But what if I mix this syntax with constructor initialization of a derived class :

class base {
 int id;
 public:
 base(int id): id(id){}
};

class dri : public base {
 int base;
 public:
 dri(int id): base(id){}
};

In the example above under the derived class, is base(id){} referring to int base or class base ? I assume it is referring to int base since is' not compiling. How can I make it refer to class base ?

Edit:

Second question, let's say you look at a random C++ code which looks like this:

class base {
 int id;
 public:
 base(int id): id(id){}
};

How can you tell if id(id){} is initializing a local variable or initializing another classes constructor?

Answer 1

Don't reuse the identifier base is the simplest advice.

More complex would be use scope resolution:

dri(int id): ::base(id){}
              ^
              use base from the global namespace

Post question edit answer:

The most recently defined use of an identifier will be used over definitions in outer scopes unless an outer scope is explicitly specified. There is no good way to tell which you will get without acting like the compiler and building a graph of what identifiers are defined and where and performing the resolution yourself.

What you've run up against is exactly the same as

int string; 
string test; 

by the time the compiler reaches string test , the meaning of string has been changed by the programmer from a type to a variable of type int . There is no solution for this other than don't do it.

This brings us back to the opening point: Don't reuse identifiers in encompassed scopes without good reason. Someone will screw it up.