clamp_cast.h

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/* Copyright (C) 2026 Olly Betts
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#ifndef XAPIAN_INCLUDED_CLAMP_CAST_H
#define XAPIAN_INCLUDED_CLAMP_CAST_H
 
#include <algorithm>
#include <limits>
 
template<typename T, typename U>
T
clamp_cast(U value)
{
    // Add a suitably-typed zero to each argument we pass to std::clamp to get
    // everything in an appropriate common type via C++ type promotion rules.
    auto v = value + T{0};
    auto min = std::numeric_limits<T>::min() + U{0};
    auto max = std::numeric_limits<T>::max() + U{0};
    return static_cast<T>(std::clamp(v, min, max));
}
 
#endif /* XAPIAN_INCLUDED_CLAMP_CAST_H */