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Method 3.2: Implement a Range Adaptor with arguments
  1. Provide a range for your return type, for example:
    #include <boost/range/adaptor/argument_fwd.hpp>
    #include <boost/range/iterator_range.hpp>
    #include <boost/iterator/transform_iterator.hpp>
    
    template<typename Value>
    class replace_value
    {
    public:
        typedef const Value& result_type;
        typedef const Value& argument_type;
    
        replace_value(const Value& from, const Value& to)
            : m_from(from), m_to(to)
        {
        }
    
        const Value& operator()(const Value& x) const
        {
            return (x == m_from) ? m_to : x;
        }
    private:
        Value m_from;
        Value m_to;
    };
    
    template<typename Range>
    class replace_range
    : public boost::iterator_range<
        boost::transform_iterator<
            replace_value<typename boost::range_value<Range>::type>,
            typename boost::range_iterator<Range>::type> >
    {
    private:
        typedef typename boost::range_value<Range>::type value_type;
        typedef typename boost::range_iterator<Range>::type iterator_base;
        typedef replace_value<value_type> Fn;
        typedef boost::transform_iterator<Fn, iterator_base> replaced_iterator;
        typedef boost::iterator_range<replaced_iterator> base_t;
    
    public:
        replace_range(Range& rng, value_type from, value_type to)
            : base_t(replaced_iterator(boost::begin(rng), Fn(from,to)),
                     replaced_iterator(boost::end(rng), Fn(from,to)))
         {
         }
     };
    
  2. Implement a holder class to hold the arguments required to construct the RangeAdaptor.

The holder combines multiple parameters into one that can be passed as the right operand of operator|().

template<typename T>
class replace_holder : public boost::range_detail::holder2<T>
{
public:
    replace_holder(const T& from, const T& to)
        : boost::range_detail::holder2<T>(from, to)
    { }
private:
    void operator=(const replace_holder&);
};

  1. Define an instance of the holder with the name of the adaptor

static boost::range_detail::forwarder2<replace_holder>
replaced = boost::range_detail::forwarder2<replace_holder>();

  1. Define operator|

template<typename SinglePassRange>
inline replace_range<SinglePassRange>
operator|(SinglePassRange& rng,
          const replace_holder<typename boost::range_value<SinglePassRange>::type>& f)
{
    return replace_range<SinglePassRange>(rng, f.val1, f.val2);
}

template<typename SinglePassRange>
inline replace_range<const SinglePassRange>
operator|(const SinglePassRange& rng,
          const replace_holder<typename boost::range_value<SinglePassRange>::type>& f)
{
    return replace_range<const SinglePassRange>(rng, f.val1, f.val2);
}


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