// 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. // Private header, not to be exported #pragma once #include #include "arrow/scalar.h" #include "arrow/status.h" #include "arrow/type.h" #include "arrow/visitor_generate.h" namespace arrow { #define SCALAR_VISIT_INLINE(TYPE_CLASS) \ case TYPE_CLASS##Type::type_id: \ return visitor->Visit(internal::checked_cast(scalar), \ std::forward(args)...); /// \brief Apply the visitors Visit() method specialized to the scalar type /// /// \tparam VISITOR Visitor type that implements Visit() for all scalar types. /// \tparam ARGS Additional arguments, if any, will be passed to the Visit function after /// the `scalar` argument /// \return Status /// /// A visitor is a type that implements specialized logic for each Arrow type. /// Example usage: /// /// ``` /// class ExampleVisitor { /// arrow::Status Visit(arrow::Int32Scalar scalar) { ... } /// arrow::Status Visit(arrow::Int64Scalar scalar) { ... } /// ... /// } /// ExampleVisitor visitor; /// VisitScalarInline(some_scalar, &visitor); /// ``` template inline Status VisitScalarInline(const Scalar& scalar, VISITOR* visitor, ARGS&&... args) { switch (scalar.type->id()) { ARROW_GENERATE_FOR_ALL_TYPES(SCALAR_VISIT_INLINE); default: break; } return Status::NotImplemented("Scalar visitor for type not implemented ", scalar.type->ToString()); } #undef SCALAR_VISIT_INLINE } // namespace arrow