mapleFU commented on code in PR #117: URL: https://github.com/apache/iceberg-cpp/pull/117#discussion_r2131988573
########## src/iceberg/datum.h: ########## @@ -0,0 +1,108 @@ +/* + * Licensed to the Apache Software Foundation (ASF) under one + * or more contributor license agreements. See the NOTICE file + * distributed with this work for additional information + * regarding copyright ownership. The ASF licenses this file + * to you under the Apache License, Version 2.0 (the + * "License"); you may not use this file except in compliance + * with the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, + * software distributed under the License is distributed on an + * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY + * KIND, either express or implied. See the License for the + * specific language governing permissions and limitations + * under the License. + */ + +#pragma once + +#include <compare> +#include <memory> +#include <string> +#include <variant> +#include <vector> + +#include "iceberg/result.h" +#include "iceberg/type.h" + +namespace iceberg { + +/// \brief Exception type for values that are below the minimum allowed value for a +/// primitive type. +/// +/// When casting a value to a narrow primitive type, if the value exceeds the maximum of +/// dest type, it might be above the maximum allowed value for that type. +struct BelowMin { + bool operator==(const BelowMin&) const = default; + std::strong_ordering operator<=>(const BelowMin&) const = default; +}; + +/// \brief Exception type for values that are above the maximum allowed value for a +/// primitive type. +/// +/// When casting a value to a narrow primitive type, if the value exceeds the maximum of +/// dest type, it might be above the maximum allowed value for that type. +struct AboveMax { + bool operator==(const AboveMax&) const = default; + std::strong_ordering operator<=>(const AboveMax&) const = default; +}; + +using PrimitiveLiteralValue = + std::variant<bool, // for boolean + int32_t, // for int, date + int64_t, // for long, timestamp, timestamp_tz, time + float, // for float + double, // for double + std::string, // for string Review Comment: Emmm, a tiny wrapper like this should be defined if unique_ptr<string> should be added. I'm also ok for the case ```c++ struct StringLiteralValue { StringLiteralValue(std::string value); StringLiteralValue(const StringLiteralValue&); StringLiteralValue(StringLiteralValue&&) noexcept; const std::string& str() const { return *value_; } bool operator==(const StringLiteralValue&) const; std::strong_ordering operator<=>(const StringLiteralValue&) const; private: std::unique_ptr<std::string> value_; }; ``` In libc++ version, `sizeof(PrimitiveLiteralValue) == 48`, since `std::vector` is large, it's still 48b after change to `StringLiteralValue`. After change to below: ```c++ template <typename T> struct LiteralValueWrapper { LiteralValueWrapper(T value); LiteralValueWrapper(const LiteralValueWrapper&); LiteralValueWrapper(LiteralValueWrapper&&) noexcept = default; const std::string& str() const { return *value_; } bool operator==(const LiteralValueWrapper<T>&) const; std::strong_ordering operator<=>(const LiteralValueWrapper<T>&) const; private: std::unique_ptr<T> value_; }; using PrimitiveLiteralValue = std::variant<bool, // for boolean int32_t, // for int, date int64_t, // for long, timestamp, timestamp_tz, time float, // for float double, // for double LiteralValueWrapper<std::string>, // for string LiteralValueWrapper<std::vector<uint8_t>>, // for binary, fixed std::array<uint8_t, 16>, // for uuid and decimal BelowMin, AboveMax>; ``` The size becomes 40B, just eliminate 8B 😅. I think it's due to C++ doesn't do any niche optimization for std::variant... -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@iceberg.apache.org For additional commands, e-mail: issues-h...@iceberg.apache.org
