apply.cpp

c++编程思想2TICPP-2nd-ed-Vol-two.zip

//: C07:Apply.cpp
// From "Thinking in C++, Volume 2", by Bruce Eckel & Chuck Allison.
// (c) 1995-2004 MindView, Inc. All Rights Reserved.
// See source code use permissions stated in the file 'License.txt',
// distributed with the code package available at www.MindView.net.
// Using simple iteration.
#include <iostream>
#include <vector>
#include <iterator>
using namespace std;

template<class Cont, class PtrMemFun>
void apply(Cont& c, PtrMemFun f) {
  typename Cont::iterator it = c.begin();
  while(it != c.end()) {
    ((*it).*f)(); // Alternate form
    ++it;
  }
}

class Z {
  int i;
public:
  Z(int ii) : i(ii) {}
  void g() { ++i; }
  friend ostream& operator<<(ostream& os, const Z& z) {
    return os << z.i;
  }
};

int main() {
  ostream_iterator<Z> out(cout, " ");
  vector<Z> vz;
  for(int i = 0; i < 10; i++)
    vz.push_back(Z(i));
  copy(vz.begin(), vz.end(), out);
  cout << endl;
  apply(vz, &Z::g);
  copy(vz.begin(), vz.end(), out);
} ///:~