1.. Copyright David Abrahams 2006. Distributed under the Boost 2.. Software License, Version 1.0. (See accompanying 3.. file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) 4 5Example 6....... 7 8This example prints an array of characters, using 9``indirect_iterator`` to access the array of characters through an 10array of pointers. Next ``indirect_iterator`` is used with the 11``transform`` algorithm to copy the characters (incremented by one) to 12another array. A constant indirect iterator is used for the source and 13a mutable indirect iterator is used for the destination. The last part 14of the example prints the original array of characters, but this time 15using the ``make_indirect_iterator`` helper function. 16 17 18:: 19 20 char characters[] = "abcdefg"; 21 const int N = sizeof(characters)/sizeof(char) - 1; // -1 since characters has a null char 22 char* pointers_to_chars[N]; // at the end. 23 for (int i = 0; i < N; ++i) 24 pointers_to_chars[i] = &characters[i]; 25 26 // Example of using indirect_iterator 27 28 boost::indirect_iterator<char**, char> 29 indirect_first(pointers_to_chars), indirect_last(pointers_to_chars + N); 30 31 std::copy(indirect_first, indirect_last, std::ostream_iterator<char>(std::cout, ",")); 32 std::cout << std::endl; 33 34 35 // Example of making mutable and constant indirect iterators 36 37 char mutable_characters[N]; 38 char* pointers_to_mutable_chars[N]; 39 for (int j = 0; j < N; ++j) 40 pointers_to_mutable_chars[j] = &mutable_characters[j]; 41 42 boost::indirect_iterator<char* const*> mutable_indirect_first(pointers_to_mutable_chars), 43 mutable_indirect_last(pointers_to_mutable_chars + N); 44 boost::indirect_iterator<char* const*, char const> const_indirect_first(pointers_to_chars), 45 const_indirect_last(pointers_to_chars + N); 46 47 std::transform(const_indirect_first, const_indirect_last, 48 mutable_indirect_first, std::bind1st(std::plus<char>(), 1)); 49 50 std::copy(mutable_indirect_first, mutable_indirect_last, 51 std::ostream_iterator<char>(std::cout, ",")); 52 std::cout << std::endl; 53 54 55 // Example of using make_indirect_iterator() 56 57 std::copy(boost::make_indirect_iterator(pointers_to_chars), 58 boost::make_indirect_iterator(pointers_to_chars + N), 59 std::ostream_iterator<char>(std::cout, ",")); 60 std::cout << std::endl; 61 62 63The output is:: 64 65 a,b,c,d,e,f,g, 66 b,c,d,e,f,g,h, 67 a,b,c,d,e,f,g, 68 69 70The source code for this example can be found `here`__. 71 72__ ../example/indirect_iterator_example.cpp 73 74