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/*
* Copyright (c) 2020-2021, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in input and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of input code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/Platform.h>
#include <AK/StdLibExtras.h>
namespace AK {
template<typename OutputType, typename InputType>
ALWAYS_INLINE bool is(InputType& input)
{
if constexpr (requires { input.template fast_is<OutputType>(); }) {
return input.template fast_is<OutputType>();
}
return dynamic_cast<CopyConst<InputType, OutputType>*>(&input);
}
template<typename OutputType, typename InputType>
ALWAYS_INLINE bool is(InputType* input)
{
return input && is<OutputType>(*input);
}
template<typename OutputType, typename InputType>
ALWAYS_INLINE CopyConst<InputType, OutputType>* downcast(InputType* input)
{
static_assert(IsBaseOf<InputType, OutputType>::value);
ASSERT(!input || is<OutputType>(*input));
return static_cast<CopyConst<InputType, OutputType>*>(input);
}
template<typename OutputType, typename InputType>
ALWAYS_INLINE CopyConst<InputType, OutputType>& downcast(InputType& input)
{
static_assert(IsBaseOf<InputType, OutputType>::value);
ASSERT(is<OutputType>(input));
return static_cast<CopyConst<InputType, OutputType>&>(input);
}
}
using AK::downcast;
using AK::is;
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