Function retrieve

include/function2/function2.hpp:485–494

/// The retriever when the object is allocated inplace
template <typename T, typename Accessor>
FU2_DETAIL_CXX14_CONSTEXPR auto retrieve(std::true_type /*is_inplace*/,
                                         Accessor from,
                                         std::size_t from_capacity) {
  using type = transfer_const_t<Accessor, transfer_volatile_t<Accessor, void>>*;

  /// Process the command by using the data inside the internal capacity
  auto storage = &(from->inplace_storage_);
  auto inplace = const_cast<void*>(static_cast<type>(storage));
  return type(std::align(alignof(T), sizeof(T), inplace, from_capacity));
}

/// The retriever which is used when the object is allocated
/// through the allocator