xapian-core  1.4.21
min_non_zero.h
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1 
4 /* Copyright (C) 2018 Olly Betts
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24 
25 #ifndef XAPIAN_INCLUDED_MIN_NON_ZERO_H
26 #define XAPIAN_INCLUDED_MIN_NON_ZERO_H
27 
28 #include <algorithm>
29 
34 template<typename T>
35 constexpr typename std::enable_if<std::is_unsigned<T>::value, T>::type
36 min_non_zero(const T& a, const T& b)
37 {
38  // To achieve the effect we want, we find the *maximum* after negating each
39  // of the values (which for an unsigned type leaves 0 alone but flips the
40  // order of all other values), then negate the answer.
41  return -std::max(-a, -b);
42 }
43 
44 #endif // XAPIAN_INCLUDED_MIN_NON_ZERO_H
constexpr std::enable_if< std::is_unsigned< T >::value, T >::type min_non_zero(const T &a, const T &b)
Return the smaller of two unsigned integers which isn&#39;t zero.
Definition: min_non_zero.h:36