wgtmac commented on code in PR #177: URL: https://github.com/apache/iceberg-cpp/pull/177#discussion_r2376158453
########## src/iceberg/expression/term.cc: ########## @@ -0,0 +1,161 @@ +/* + * 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/term.h" + +#include <format> + +#include "iceberg/exception.h" +#include "iceberg/result.h" +#include "iceberg/schema.h" +#include "iceberg/transform.h" +#include "iceberg/util/checked_cast.h" +#include "iceberg/util/macros.h" + +namespace iceberg { + +Bound::~Bound() = default; + +BoundTerm::~BoundTerm() = default; + +Reference::~Reference() = default; + +template <typename B> +Result<std::shared_ptr<B>> Unbound<B>::Bind(const Schema& schema) const { + return Bind(schema, /*case_sensitive=*/true); +} + +// NamedReference implementation +NamedReference::NamedReference(std::string field_name) + : field_name_(std::move(field_name)) {} + +NamedReference::~NamedReference() = default; + +Result<std::shared_ptr<BoundReference>> NamedReference::Bind(const Schema& schema, + bool case_sensitive) const { + if (!case_sensitive) { + return NotImplemented("case-insensitive lookup is not implemented"); + } + + auto field_opt = schema.GetFieldByName(field_name_); + if (!field_opt.has_value()) { + return InvalidExpression("Cannot find field '{}' in struct: {}", field_name_, + schema.ToString()); + } + + return std::make_shared<BoundReference>(field_opt->get()); +} + +std::string NamedReference::ToString() const { + return std::format("ref(name=\"{}\")", field_name_); +} + +// BoundReference implementation +BoundReference::BoundReference(SchemaField field) : field_(std::move(field)) {} + +BoundReference::~BoundReference() = default; + +std::string BoundReference::ToString() const { + return std::format("ref(id={}, type={})", field_.field_id(), field_.type()->ToString()); +} + +Result<Literal::Value> BoundReference::Evaluate(const StructLike& data) const { + return NotImplemented("BoundReference::Evaluate(StructLike) not implemented"); +} + +bool BoundReference::Equals(const BoundTerm& other) const { + if (other.kind() != Term::Kind::kReference) { + return false; + } + + const auto& other_ref = internal::checked_cast<const BoundReference&>(other); + return field_.field_id() == other_ref.field_.field_id() && + field_.optional() == other_ref.field_.optional() && + *field_.type() == *other_ref.field_.type(); +} + +// UnboundTransform implementation +UnboundTransform::UnboundTransform(std::shared_ptr<NamedReference> ref, + std::shared_ptr<Transform> transform) + : ref_(std::move(ref)), transform_(std::move(transform)) {} + +UnboundTransform::~UnboundTransform() = default; + +std::string UnboundTransform::ToString() const { + return std::format("{}({})", transform_->ToString(), ref_->ToString()); +} + +Result<std::shared_ptr<BoundTransform>> UnboundTransform::Bind( + const Schema& schema, bool case_sensitive) const { + ICEBERG_ASSIGN_OR_RAISE(auto bound_ref, ref_->Bind(schema, case_sensitive)); + ICEBERG_ASSIGN_OR_RAISE(auto transform_func, transform_->Bind(bound_ref->type())); + return std::make_shared<BoundTransform>(std::move(bound_ref), transform_, + std::move(transform_func)); +} + +// BoundTransform implementation +BoundTransform::BoundTransform(std::shared_ptr<BoundReference> ref, + std::shared_ptr<Transform> transform, + std::shared_ptr<TransformFunction> transform_func) + : ref_(std::move(ref)), + transform_(std::move(transform)), + transform_func_(std::move(transform_func)) {} + +BoundTransform::~BoundTransform() = default; + +std::string BoundTransform::ToString() const { + return std::format("{}({})", transform_->ToString(), ref_->ToString()); +} + +Result<Literal::Value> BoundTransform::Evaluate(const StructLike& data) const { + throw IcebergError("BoundTransform::Evaluate(StructLike) not implemented"); +} + +bool BoundTransform::MayProduceNull() const { + // transforms must produce null for null input values + // transforms may produce null for non-null inputs when not order-preserving + // FIXME: add Transform::is_order_preserving() + return ref_->MayProduceNull(); // || !transform_->is_order_preserving(); +} + +std::shared_ptr<Type> BoundTransform::type() const { + return transform_func_->ResultType(); +} + +bool BoundTransform::Equals(const BoundTerm& other) const { + if (other.kind() == Term::Kind::kTransform) { + const auto& other_transform = internal::checked_cast<const BoundTransform&>(other); + return *ref_ == *other_transform.ref_ && *transform_ == *other_transform.transform_; Review Comment: I think the problem is that Equals can have virtual inheritance but `operator==` does not. So we depend on `Equals` to implement type-specific logic and also implement `operator==` to make it easier to use. -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
