min_non_zero.h

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/* Copyright (C) 2018,2023 Olly Betts
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#ifndef XAPIAN_INCLUDED_MIN_NON_ZERO_H
#define XAPIAN_INCLUDED_MIN_NON_ZERO_H
 
#include <algorithm>
#include <type_traits>
 
#include "negate_unsigned.h"
 
template<typename T>
constexpr typename std::enable_if_t<std::is_unsigned_v<T>, T>
min_non_zero(const T& a, const T& b)
{
    // To achieve the effect we want, we find the *maximum* after negating each
    // of the values (which for an unsigned type leaves 0 alone but flips the
    // order of all other values), then negate the answer.
    return negate_unsigned(std::max(negate_unsigned(a), negate_unsigned(b)));
}
 
#endif // XAPIAN_INCLUDED_MIN_NON_ZERO_H