| 1 | //===----------------------------------------------------------------------===// |
| 2 | // DuckDB |
| 3 | // |
| 4 | // duckdb/common/optional_ptr.hpp |
| 5 | // |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #pragma once |
| 10 | |
| 11 | #include "duckdb/common/exception.hpp" |
| 12 | #include "duckdb/common/unique_ptr.hpp" |
| 13 | |
| 14 | namespace duckdb { |
| 15 | |
| 16 | template <class T> |
| 17 | class optional_ptr { |
| 18 | public: |
| 19 | optional_ptr() : ptr(nullptr) { |
| 20 | } |
| 21 | optional_ptr(T *ptr_p) : ptr(ptr_p) { // NOLINT: allow implicit creation from pointer |
| 22 | } |
| 23 | optional_ptr(const unique_ptr<T> &ptr_p) : ptr(ptr_p.get()) { // NOLINT: allow implicit creation from unique pointer |
| 24 | } |
| 25 | |
| 26 | void CheckValid() const { |
| 27 | if (!ptr) { |
| 28 | throw InternalException("Attempting to dereference an optional pointer that is not set" ); |
| 29 | } |
| 30 | } |
| 31 | |
| 32 | operator bool() const { |
| 33 | return ptr; |
| 34 | } |
| 35 | T &operator*() { |
| 36 | CheckValid(); |
| 37 | return *ptr; |
| 38 | } |
| 39 | const T &operator*() const { |
| 40 | CheckValid(); |
| 41 | return *ptr; |
| 42 | } |
| 43 | T *operator->() { |
| 44 | CheckValid(); |
| 45 | return ptr; |
| 46 | } |
| 47 | const T *operator->() const { |
| 48 | CheckValid(); |
| 49 | return ptr; |
| 50 | } |
| 51 | T *get() { |
| 52 | // CheckValid(); |
| 53 | return ptr; |
| 54 | } |
| 55 | const T *get() const { |
| 56 | // CheckValid(); |
| 57 | return ptr; |
| 58 | } |
| 59 | // this looks dirty - but this is the default behavior of raw pointers |
| 60 | T *get_mutable() const { |
| 61 | // CheckValid(); |
| 62 | return ptr; |
| 63 | } |
| 64 | |
| 65 | bool operator==(const optional_ptr<T> &rhs) const { |
| 66 | return ptr == rhs.ptr; |
| 67 | } |
| 68 | |
| 69 | bool operator!=(const optional_ptr<T> &rhs) const { |
| 70 | return ptr != rhs.ptr; |
| 71 | } |
| 72 | |
| 73 | private: |
| 74 | T *ptr; |
| 75 | }; |
| 76 | |
| 77 | } // namespace duckdb |
| 78 | |