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//
 
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// Copyright (c) 2026 Michael Vandeberg
 
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//
 
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
 
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
 
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//
 
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// Official repository: https://github.com/cppalliance/capy
 
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//
 
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#ifndef BOOST_CAPY_DETAIL_SERVICE_SLOT_HPP
 
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#define BOOST_CAPY_DETAIL_SERVICE_SLOT_HPP
 
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#include <atomic>
 
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#include <cstddef>
 
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namespace boost {
 
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namespace capy {
 
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namespace detail {
 
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/* Slot ID infrastructure for O(1) service lookup.
 
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   Each distinct service type T gets a unique integer index via
 
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   service_slot<T>(). The index is assigned on first call from a
 
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   global atomic counter and cached in a function-local static.
 
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   Cross-DLL safety relies on COMDAT deduplication (same mechanism
 
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   as type_id_impl<T>::tag).
 
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*/
 
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inline std::atomic<std::size_t> next_service_slot{0};
 
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template<class T>
 
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std::size_t
 
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service_slot() noexcept
 
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{
 
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    static const std::size_t id =
 
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        next_service_slot.fetch_add(1, std::memory_order_relaxed);
 
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    return id;
 
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}
 
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} // namespace detail
 
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} // namespace capy
 
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} // namespace boost
 
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#endif