boost/function_output_iterator.hpp

   1 // (C) Copyright Jeremy Siek 2001.
   2 // Distributed under the Boost Software License, Version 1.0. (See
   3 // accompanying file LICENSE_1_0.txt or copy at
   4 // http://www.boost.org/LICENSE_1_0.txt)
   5
   6 // Revision History:
   7
   8 // 27 Feb 2001   Jeremy Siek
   9 //      Initial checkin.
  10
  11 #ifndef BOOST_FUNCTION_OUTPUT_ITERATOR_HPP
  12 #define BOOST_FUNCTION_OUTPUT_ITERATOR_HPP
  13
  14 #include <iterator>
  15
  16 namespace boost {
  17
  18   template <class UnaryFunction>
  19   class function_output_iterator {
  20     typedef function_output_iterator self;
  21   public:
  22     typedef std::output_iterator_tag iterator_category;
  23     typedef void                value_type;
  24     typedef void                difference_type;
  25     typedef void                pointer;
  26     typedef void                reference;
  27
  28     explicit function_output_iterator() {}
  29
  30     explicit function_output_iterator(const UnaryFunction& f)
  31       : m_f(f) {}
  32
  33     struct output_proxy {
  34       output_proxy(UnaryFunction& f) : m_f(f) { }
  35       template <class T> output_proxy& operator=(const T& value) {
  36         m_f(value);
  37         return *this;
  38       }
  39       UnaryFunction& m_f;
  40     };
  41     output_proxy operator*() { return output_proxy(m_f); }
  42     self& operator++() { return *this; }
  43     self& operator++(int) { return *this; }
  44   private:
  45     UnaryFunction m_f;
  46   };
  47
  48   template <class UnaryFunction>
  49   inline function_output_iterator<UnaryFunction>
  50   make_function_output_iterator(const UnaryFunction& f = UnaryFunction()) {
  51     return function_output_iterator<UnaryFunction>(f);
  52   }
  53
  54 } // namespace boost
  55
  56 #endif // BOOST_FUNCTION_OUTPUT_ITERATOR_HPP