47 lines
1.3 KiB
C++
47 lines
1.3 KiB
C++
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/*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* Copyright 2018, Danny Robson <danny@nerdcruft.net>
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*/
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#pragma once
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namespace util::scoped {
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///////////////////////////////////////////////////////////////////////////
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/// restores a referenced target variable to its original value at
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/// destruction time. the type must be copyable.
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template <typename ValueT>
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class restore {
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public:
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restore (ValueT &_target):
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m_target (_target),
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m_value (_target)
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{ ; }
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~restore ()
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{
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m_target = m_value;
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}
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private:
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ValueT &m_target;
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ValueT const m_value;
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};
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//-------------------------------------------------------------------------
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template <typename ValueT>
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restore (ValueT&) -> restore<ValueT>;
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}
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