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/*
* Copyright (C) 2024 Apple Inc. All rights reserved.
* Copyright (C) 2026 Samuel Weinig <sam@webkit.org>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source 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 APPLE INC. AND ITS 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 APPLE INC. OR ITS 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 <cstddef>
namespace WTF {
// `IsIncreasing` is a utility to check that a series of numbers are increasing.
//
// On example usage is for generated code to check the relative order of the members of a struct:
//
// Given struct:
//
// struct Foo {
// int a;
// int b;
// int c;
// };
//
// You can statically assert:
//
// static_assert(IsIncreasing<
// 0
// , offsetof(Foo, a)
// , offsetof(Foo, b)
// , offsetof(Foo, c)
// >);
template<size_t...>
struct IsIncreasingChecker;
template<size_t index>
struct IsIncreasingChecker<index> {
static constexpr bool value = true;
};
template<size_t firstIndex, size_t secondIndex, size_t... remainingIndices>
struct IsIncreasingChecker<firstIndex, secondIndex, remainingIndices...> {
static constexpr bool value = firstIndex > secondIndex ? false : IsIncreasingChecker<secondIndex, remainingIndices...>::value;
};
template<size_t... indices>
constexpr bool IsIncreasing = IsIncreasingChecker<indices...>::value;
} // namespace WTF
using WTF::IsIncreasing;
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