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