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/*
Copyright (C) 2006 - 2015 Evan Teran
evan.teran@gmail.com
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef STRING_HASH_H_20110823_
#define STRING_HASH_H_20110823_
#include <cstddef>
#include <cstdint>
#include <type_traits>
namespace edb {
namespace detail {
template <std::size_t N, std::size_t n>
constexpr typename std::enable_if<N <= 9 && n == 0, uint64_t>::type string_hash(const char (&)[N]) {
return 0;
}
template <std::size_t N, std::size_t n = N - 1>
constexpr typename std::enable_if<N <= 9 && n != 0, uint64_t>::type string_hash(const char (&array)[N]) {
return string_hash<N, n - 1>(array) | ((array[n - 1] & 0xffull) << (8 * (n - 1)));
}
}
template <std::size_t N>
constexpr typename std::enable_if<N <= 9, uint64_t>::type string_hash(const char (&array)[N]) {
return detail::string_hash(array);
}
}
#endif
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