zhjwpku commented on code in PR #58: URL: https://github.com/apache/iceberg-cpp/pull/58#discussion_r2040673571
########## test/expression_test.cc: ########## @@ -0,0 +1,67 @@ +/* + * 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. + */ + +#include "iceberg/expression.h" + +#include <memory> + +#include <gtest/gtest.h> + +namespace iceberg { + +TEST(TrueFalseTest, Basi) { Review Comment: %s/Basi/Basic/ ########## test/expression_test.cc: ########## @@ -0,0 +1,67 @@ +/* + * 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. + */ + +#include "iceberg/expression.h" + +#include <memory> + +#include <gtest/gtest.h> + +namespace iceberg { + +TEST(TrueFalseTest, Basi) { + // Test negation of False returns True + const std::shared_ptr<False> false_instance = False::Instance(); Review Comment: maybe use auto to deduce? I see `False::Instance()` returns a ref of shared_ptr. ########## src/iceberg/expression.h: ########## @@ -0,0 +1,167 @@ +/* + * 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 + +/// \file iceberg/expression.h +/// Expression interface for Iceberg table operations. + +#include <memory> +#include <string> + +#include "iceberg/expected.h" +#include "iceberg/iceberg_export.h" +#include "iceberg/result.h" + +namespace iceberg { + +/// \brief Type alias for shared pointer to Expression +class Expression; +using ExpressionPtr = std::shared_ptr<Expression>; + +/// \brief Represents a boolean expression tree. +class ICEBERG_EXPORT Expression { + public: + /// Operation types for expressions + enum class Operation { + kTrue, + kFalse, + kIsNull, + kNotNull, + kIsNan, + kNotNan, + kLt, + kLtEq, + kGt, + kGtEq, + kEq, + kNotEq, + kIn, + kNotIn, + kNot, + kAnd, + kOr, + kStartsWith, + kNotStartsWith, + kCount, + kCountStar, + kMax, + kMin + }; + + virtual ~Expression() = default; + + /// \brief Returns the operation for an expression node. + virtual Operation op() const = 0; + + /// \brief Returns the negation of this expression, equivalent to not(this). + virtual Result<ExpressionPtr> Negate() const { + return unexpected( + Error(ErrorKind::kInvalidExpression, "Expression cannot be negated")); + } + + /// \brief Returns whether this expression will accept the same values as another. + /// \param other another expression + /// \return true if the expressions are equivalent + virtual bool Equals(const Expression& other) const { + // only bound predicates can be equivalent + return false; + } + + virtual std::string ToString() const { return "Expression"; } +}; + +/// \brief An Expression that is always true. +/// +/// Represents a boolean predicate that always evaluates to true. +class ICEBERG_EXPORT True : public Expression { + public: + /// \brief Returns the singleton instance + static const std::shared_ptr<True>& Instance(); + + Operation op() const override { return Operation::kTrue; } + + std::string ToString() const override { return "true"; } + + Result<ExpressionPtr> Negate() const override; + + bool Equals(const Expression& other) const override { + return other.op() == Operation::kTrue; + } + + private: + constexpr True() = default; +}; + +/// \brief An expression that is always false. +class ICEBERG_EXPORT False : public Expression { + public: + /// \brief Returns the singleton instance + static const std::shared_ptr<False>& Instance(); + + Operation op() const override { return Operation::kFalse; } + + std::string ToString() const override { return "false"; } + + Result<ExpressionPtr> Negate() const override; + + bool Equals(const Expression& other) const override { + return other.op() == Operation::kFalse; + } + + private: + constexpr False() = default; +}; + +/// \brief An Expression that represents a logical AND operation between two expressions. +/// +/// This expression evaluates to true if and only if both of its child expressions +/// evaluate to true. +class ICEBERG_EXPORT And : public Expression { + public: + /// \brief Constructs an And expression from two sub-expressions. + /// + /// @param left The left operand of the AND expression Review Comment: We use backslash other than @ for the comments, maybe stick to the same rule. I see you are using backslash in `Expression`, I guess it's an oversight here ;) -- 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
