forked from boostorg/range
60 lines
1.5 KiB
Plaintext
60 lines
1.5 KiB
Plaintext
[/
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Copyright 2010 Neil Groves
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Distributed under the Boost Software License, Version 1.0.
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(See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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/]
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[section:transformed transformed]
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[table
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[[Syntax] [Code]]
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[[Pipe] [`rng | boost::adaptors::transformed(fun)`]]
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[[Function] [`boost::adaptors::transform(rng, fun)`]]
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]
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* [*Precondition:] The `value_type` of the range is convertible to the argument type of `fun`.
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* [*Postcondition:] For all elements `x` in the returned range, `x` is the result of `fun(y)` where `y` is the corresponding element in the original range.
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* [*Throws:] Whatever the copy-constructor of `fun` might throw.
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* [*Range Category:] __single_pass_range__
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* [*Range Return Type:] `boost::transformed_range<typeof(rng)>`
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* [*Returned Range Category:] The range category of `rng`.
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[section:transformed_example transformed example]
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``
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#include <boost/range/adaptor/transformed.hpp>
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#include <boost/range/algorithm/copy.hpp>
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#include <boost/assign.hpp>
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#include <algorithm>
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#include <iostream>
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#include <vector>
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struct double_int
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{
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typedef int result_type;
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int operator()(int x) const { return x * 2; }
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};
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int main(int argc, const char* argv[])
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{
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using namespace boost::adaptors;
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using namespace boost::assign;
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std::vector<int> input;
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input += 1,2,3,4,5,6,7,8,9,10;
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boost::copy(
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input | transformed(double_int()),
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std::ostream_iterator<int>(std::cout, ","));
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return 0;
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}
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``
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[endsect]
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This would produce the output:
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``
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2,4,6,8,10,12,14,16,18,20
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``
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[endsect]
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