Source/WTF/wtf/VectorHash.h

/*
 * Copyright (C) 2019 Apple Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 * 1. Redistributions of source code must retain the above copyright
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 * 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.
 *
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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#pragma once

#include "HashFunctions.h"
#include "HashTraits.h"
#include "Hasher.h"

namespace WTF {

template<typename T, size_t inlineCapacity>
struct VectorHash {
    static unsigned hash(const Vector<T, inlineCapacity>& vector)
    {
        IntegerHasher hasher;
        for (const auto& value : vector)
            hasher.add(DefaultHash<T>::Hash::hash(value));
        return hasher.hash();
    }
    static bool equal(const Vector<T, inlineCapacity>& a, const Vector<T, inlineCapacity>& b)
    {
        return a == b;
    }
    static constexpr bool safeToCompareToEmptyOrDeleted = true;
};

template<typename T, size_t inlineCapacity>
struct DefaultHash<Vector<T, inlineCapacity>> {
    using Hash = VectorHash<T, inlineCapacity>;
};

}