issue8.cpp
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/*=============================================================================
Copyright (c) 2017 Paul Fultz II
issue8.cpp
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)
==============================================================================*/
#include "test.hpp"
#include <vector>
#include <boost/hof/pipable.hpp>
#include <boost/hof/placeholders.hpp>
#include <algorithm>
struct filter_fn
{
template<class Input, class P>
Input operator()(Input input, P pred) const
{
Input output(input.size());
output.erase(
::std::copy_if(
::std::begin(input),
::std::end(input),
::std::begin(output),
pred
),
::std::end(output)
);
return output;
}
};
static constexpr boost::hof::pipable_adaptor<filter_fn> filter = {};
BOOST_HOF_TEST_CASE()
{
std::vector<int> data;
for(int i=0;i<6;i++)
{
data.push_back(i);
}
std::vector<int> r1 = data | filter(boost::hof::_1 > 1);
BOOST_HOF_TEST_CHECK(r1.size() == 4);
std::vector<int> r2 = filter(data, boost::hof::_1 > 1);
BOOST_HOF_TEST_CHECK(r2.size() == 4);
}