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#pragma once
#include "asl/meta.hpp"
#include "asl/allocator.hpp"
#include "asl/annotations.hpp"
namespace asl
{
template<is_object T, allocator Allocator = DefaultAllocator>
class buffer
{
T* m_data{};
isize_t m_capacity{};
// bit 63 : 0 = on heap, 1 = inline
// bits [62:56] : size when inline
// bits [52:0] : size when on heap
size_t m_size_encoded{};
ASL_NO_UNIQUE_ADDRESS Allocator m_allocator;
static_assert(align_of<T> <= align_of<T*>);
static_assert(align_of<T*> == align_of<isize_t>);
static_assert(align_of<T*> == align_of<size_t>);
public:
static constexpr isize_t kInlineCapacity = []() {
// 1 byte is used for size inline in m_size_encoded.
// This is enough because we have at most 24 bytes available,
// so 23 chars of capacity.
const isize_t available_size = size_of<T*> + size_of<isize_t> + size_of<size_t> - 1;
return available_size / size_of<T>;
}();
constexpr buffer() requires default_constructible<Allocator> = default;
explicit constexpr buffer(Allocator allocator)
: m_allocator{ASL_MOVE(allocator)}
{}
};
} // namespace asl
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