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author | koe <ukoe@protonmail.com> | 2022-12-24 19:15:27 -0600 |
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committer | koe <ukoe@protonmail.com> | 2022-12-24 19:15:27 -0600 |
commit | e5aa058a8d9052bf6f4b58ba7bb9074909b6040a (patch) | |
tree | 1321faf49797f305553710f6a7ed0bc6cacad83f /src | |
parent | add compare_func() method so user-defined comparison functions are easier to use (diff) | |
download | monero-e5aa058a8d9052bf6f4b58ba7bb9074909b6040a.tar.xz |
vtnerd review comments
Diffstat (limited to 'src')
-rw-r--r-- | src/common/container_helpers.h | 79 |
1 files changed, 60 insertions, 19 deletions
diff --git a/src/common/container_helpers.h b/src/common/container_helpers.h index 2c526bb4e..238f0ddad 100644 --- a/src/common/container_helpers.h +++ b/src/common/container_helpers.h @@ -36,10 +36,8 @@ //standard headers #include <algorithm> -#include <functional> #include <unordered_map> #include <utility> -#include <vector> //forward declarations @@ -49,23 +47,50 @@ namespace tools /// convert a binary comparison function to a functor template <typename T, typename ComparisonOpT = bool(const T &a, const T &b)> -inline auto compare_func(const ComparisonOpT &comparison_function) +inline auto compare_func(ComparisonOpT comparison_op_func) { - return [&comparison_function](const T &a, const T &b) -> bool { return comparison_function(a, b); }; + static_assert( + std::is_same< + bool, + decltype( + comparison_op_func( + std::declval<std::remove_cv_t<T>>(), + std::declval<std::remove_cv_t<T>>() + ) + ) + >::value, + "invalid callable - expected callable in form bool(T, T)" + ); + + return [func = std::move(comparison_op_func)] (const T &a, const T &b) -> bool { return func(a, b); }; } /// test if a container is sorted and unique according to a comparison criteria (defaults to operator<) /// NOTE: ComparisonOpT must establish 'strict weak ordering' https://en.cppreference.com/w/cpp/named_req/Compare template <typename T, typename ComparisonOpT = std::less<typename T::value_type>> -bool is_sorted_and_unique(const T &container, const ComparisonOpT &ComparisonOp = ComparisonOpT{}) +bool is_sorted_and_unique(const T &container, ComparisonOpT comparison_op = ComparisonOpT{}) { - if (!std::is_sorted(container.begin(), container.end(), ComparisonOp)) + using ValueT = typename T::value_type; + static_assert( + std::is_same< + bool, + decltype( + comparison_op( + std::declval<std::remove_cv_t<ValueT>>(), + std::declval<std::remove_cv_t<ValueT>>() + ) + ) + >::value, + "invalid callable - expected callable in form bool(ValueT, ValueT)" + ); + + if (!std::is_sorted(container.begin(), container.end(), comparison_op)) return false; if (std::adjacent_find(container.begin(), container.end(), - [&ComparisonOp](const typename T::value_type &a, const typename T::value_type &b) -> bool + [comparison_op](const ValueT &a, const ValueT &b) -> bool { - return !ComparisonOp(a, b) && !ComparisonOp(b, a); + return !comparison_op(a, b) && !comparison_op(b, a); }) != container.end()) return false; @@ -75,20 +100,28 @@ bool is_sorted_and_unique(const T &container, const ComparisonOpT &ComparisonOp /// specialization for raw function pointers template <typename T> bool is_sorted_and_unique(const T &container, - bool (*const ComparisonOpFunc)(const typename T::value_type &a, const typename T::value_type &b)) + bool (*const comparison_op_func)(const typename T::value_type &a, const typename T::value_type &b)) { - return is_sorted_and_unique(container, compare_func<typename T::value_type>(ComparisonOpFunc)); + return is_sorted_and_unique(container, compare_func<typename T::value_type>(comparison_op_func)); } /// convenience wrapper for checking if a mapped object is mapped to a key embedded in that object /// example: std::unorderd_map<rct::key, std::pair<rct::key, rct::xmr_amount>> where the map key is supposed to /// reproduce the pair's rct::key; use the predicate to get the pair's rct::key element -template <typename KeyT, typename ValueT> -bool keys_match_internal_values(const std::unordered_map<KeyT, ValueT> &map, - const std::function< - const typename std::unordered_map<KeyT, ValueT>::key_type& - (const typename std::unordered_map<KeyT, ValueT>::mapped_type&) - > &get_internal_key_func) +template <typename KeyT, typename ValueT, typename PredT> +bool keys_match_internal_values(const std::unordered_map<KeyT, ValueT> &map, PredT get_internal_key_func) { + static_assert( + std::is_same< + std::remove_cv_t<std::remove_reference_t< + KeyT + >>, + std::remove_cv_t<std::remove_reference_t< + decltype(get_internal_key_func(std::declval<std::remove_cv_t<std::remove_reference_t<ValueT>>>())) + >> + >::value, + "invalid callable - expected callable in form Key(Value)" + ); + for (const auto &map_element : map) { if (!(map_element.first == get_internal_key_func(map_element.second))) @@ -105,10 +138,18 @@ typename ContainerT::value_type& add_element(ContainerT &container) return container.back(); } /// convenience erasor for unordered maps: std::erase_if(std::unordered_map) is C++20 -template <typename KeyT, typename ValueT> -void for_all_in_map_erase_if(std::unordered_map<KeyT, ValueT> &map_inout, - const std::function<bool(const typename std::unordered_map<KeyT, ValueT>::value_type&)> &predicate) +template <typename KeyT, typename ValueT, typename PredT> +void for_all_in_map_erase_if(std::unordered_map<KeyT, ValueT> &map_inout, PredT predicate) { + using MapValueT = typename std::unordered_map<KeyT, ValueT>::value_type; + static_assert( + std::is_same< + bool, + decltype(predicate(std::declval<std::remove_cv_t<std::remove_reference_t<MapValueT>>>())) + >::value, + "invalid callable - expected callable in form bool(Value)" + ); + for (auto map_it = map_inout.begin(); map_it != map_inout.end();) { if (predicate(*map_it)) |