lsst.utils  16.0-13-g80874fd
hashCombine.h
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22 #ifndef LSST_UTILS_HASH_COMBINE_H
23 #define LSST_UTILS_HASH_COMBINE_H
24 
25 #include <functional>
26 
27 namespace lsst {
28 namespace utils {
29 
31 
45 inline std::size_t hashCombine(std::size_t seed) { return seed; }
46 
47 template <typename T, typename... Rest>
48 std::size_t hashCombine(std::size_t seed, const T& value, Rest... rest) {
49  std::hash<T> hasher;
50  seed ^= hasher(value) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
51  return hashCombine(seed, rest...);
52 }
54 
55 }} // namespace lsst::utils
56 
57 #endif
Forward declarations for lsst::utils::Cache.
std::size_t hashCombine(std::size_t seed)
Combine hashes.
Definition: hashCombine.h:45