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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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