forked from boostorg/core
63 lines
1.0 KiB
Plaintext
63 lines
1.0 KiB
Plaintext
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Copyright 2018 Glen Joseph Fernandes
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(glenjofe@gmail.com)
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Distributed under the Boost Software License, Version 1.0.
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(http://www.boost.org/LICENSE_1_0.txt)
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]
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[section:exchange exchange]
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[simplesect Authors]
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* Glen Fernandes
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[endsimplesect]
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[section Overview]
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The header <boost/core/exchange.hpp> provides the function template
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`boost::exchange` which is an implementation of the `std::exchange`
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function introduced in C++14.
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[endsect]
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[section Examples]
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The following example shows `boost::exchange` used to simplify the
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implementation of a move constructor.
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```
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Node(Node&& other)
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: head_(boost::exchange(other.head_, nullptr))
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, tail_(boost::exchange(other.tail_, nullptr)) { }
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```
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[endsect]
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[section Reference]
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```
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namespace boost {
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template<class T, class U = T>
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constexpr T exchange(T& t, U&& u);
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}
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```
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[section Functions]
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[*`template<class T, class U = T> constexpr T exchange(T& t, U&& u);`]
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Equivalent to:
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```
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T v = std::move(t);
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t = std::forward<U>(u);
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return v;
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```
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[endsect]
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[endsect]
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[endsect]
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