applysequence.h

Thinking in C++ ２.０书籍源码光盘

//: C19:applySequence.h
// From Thinking in C++, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 1999
// Copyright notice in Copyright.txt
// Apply a function to an STL sequence container

// 0 arguments, any type of return value:
template<class Seq, class T, class R>
void apply(Seq& sq, R (T::*f)()) {
  typename Seq::iterator it = sq.begin();
  while(it != sq.end()) {
    ((*it)->*f)();
    it++;
  }
}

// 1 argument, any type of return value:
template<class Seq, class T, class R, class A>
void apply(Seq& sq, R(T::*f)(A), A a) {
  typename Seq::iterator it = sq.begin();
  while(it != sq.end()) {
    ((*it)->*f)(a);
    it++;
  }
}

// 2 arguments, any type of return value:
template<class Seq, class T, class R, 
         class A1, class A2>
void apply(Seq& sq, R(T::*f)(A1, A2),
    A1 a1, A2 a2) {
  typename Seq::iterator it = sq.begin();
  while(it != sq.end()) {
    ((*it)->*f)(a1, a2);
    it++;
  }
}
// Etc., to handle maximum likely arguments ///:~