min_non_zero.h

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/* Copyright (C) 2018 Olly Betts
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 * furnished to do so, subject to the following conditions:
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#ifndef XAPIAN_INCLUDED_MIN_NON_ZERO_H
#define XAPIAN_INCLUDED_MIN_NON_ZERO_H

#include <algorithm>

template<typename T>
constexpr typename std::enable_if<std::is_unsigned<T>::value, T>::type
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 -std::max(-a, -b);
}

#endif // XAPIAN_INCLUDED_MIN_NON_ZERO_H