hash.h

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/* Copyright (C) 2019 Wildfire Games.
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 * The above copyright notice and this permission notice shall be included
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#ifndef INCLUDED_HASH
#define INCLUDED_HASH
 
/**
 * This function is the same as hash_combine, i.e. allows dropping the boost dependency just for this function.
 */
template <typename T>
void hash_combine(std::size_t& seed, const T& val)
{
    seed ^= std::hash<T>()(val) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
}
 
#endif // #ifndef INCLUDED_HASH