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// Copyright (C) 2009-2012 Lorenzo Caminiti
// Distributed under the Boost Software License, Version 1.0
// (see accompanying file LICENSE_1_0.txt or a copy at
// http://www.boost.org/LICENSE_1_0.txt)
// Home at http://www.boost.org/libs/local_function
#include <boost/config.hpp>
#ifdef BOOST_NO_CXX11_LAMBDAS
# error "lambda functions required"
#else
#include <iostream>
#include <cassert>
//[expensive_copy_cxx11_lambda
struct n {
int i;
n(int _i): i(_i) {}
n(n const& x): i(x.i) { // Some time consuming copy operation.
for (unsigned i = 0; i < 10000; ++i) std::cout << '.';
}
};
int main(void) {
n x(-1);
auto f = [x]() { // Problem: Expensive copy, but if bind
assert(x.i == -1); // by `&x` then `x` is not constant.
};
f();
return 0;
}
//]
#endif // NO_LAMBDAS
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