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- .. Copyright David Abrahams 2006. Distributed under the Boost
- .. Software License, Version 1.0. (See accompanying
- .. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
- Example
- .......
- This is a simple example of using the transform_iterators class to
- generate iterators that multiply (or add to) the value returned by
- dereferencing the iterator. It would be cooler to use lambda library
- in this example.
- ::
- int x[] = { 1, 2, 3, 4, 5, 6, 7, 8 };
- const int N = sizeof(x)/sizeof(int);
- typedef boost::binder1st< std::multiplies<int> > Function;
- typedef boost::transform_iterator<Function, int*> doubling_iterator;
- doubling_iterator i(x, boost::bind1st(std::multiplies<int>(), 2)),
- i_end(x + N, boost::bind1st(std::multiplies<int>(), 2));
- std::cout << "multiplying the array by 2:" << std::endl;
- while (i != i_end)
- std::cout << *i++ << " ";
- std::cout << std::endl;
- std::cout << "adding 4 to each element in the array:" << std::endl;
- std::copy(boost::make_transform_iterator(x, boost::bind1st(std::plus<int>(), 4)),
- boost::make_transform_iterator(x + N, boost::bind1st(std::plus<int>(), 4)),
- std::ostream_iterator<int>(std::cout, " "));
- std::cout << std::endl;
- The output is::
- multiplying the array by 2:
- 2 4 6 8 10 12 14 16
- adding 4 to each element in the array:
- 5 6 7 8 9 10 11 12
- The source code for this example can be found `here`__.
- __ ../example/transform_iterator_example.cpp
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