typenamedid.cpp

来自「This is the second part of that lab manu」· C++ 代码 · 共 29 行

//: C06:TypenamedID.cpp
// From "Thinking in C++, 2nd Edition, Volume 2"
// by Bruce Eckel & Chuck Allison, (c) 2001 MindView, Inc.
// Available at www.BruceEckel.com.
// Using 'typename' to say it's a type, 
// and not something other than a type
//{L} ../TestSuite/Test

template<class T> class X {
  // Without typename, you should get an error:
  typename T::id i;
public:
  void f() { i.g(); }
};

class Y {
public:
  class id {
  public:
    void g() {}
  };
};

int main() {
  Y y;
  X<Y> xy;
  xy.f();
} ///:~