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53 lines
1.3 KiB
Plaintext
53 lines
1.3 KiB
Plaintext
[section:replaced_if replaced_if]
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[table
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[[Syntax] [Code]]
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[[Pipe] [`rng | boost::adaptors::replaced_if(pred, new_value)`]]
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[[Function] [`boost::adaptors::replace_if(rng, pred, new_value)`]]
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]
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* [*Precondition:]
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* The range `value_type` is convertible to the argument type of `pred`.
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* `new_value` is convertible to the `value_type` of the range.
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* [*Postconditions:] For all elements `x` in the returned range, the value `x` is equal to the value of `pred(y) ? new_value : y` where `y` is the corresponding element in the original range.
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* [*Range Category:] `ForwardRange`
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[section:replaced_if_example replaced_if example]
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``
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#include <boost/range/adaptor/replaced_if.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 is_even
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{
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bool operator()(int x) const { return x % 2 == 0; }
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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;
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boost::copy(
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input | replaced_if(is_even(), 10),
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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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1,10,3,10,5,10,7,10,9
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``
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[endsect]
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