r/src/expression.cpp

// Licensed to the Apache Software Foundation (ASF) under one
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// 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 "./arrow_types.h"

#if defined(ARROW_R_WITH_ARROW)

#include <arrow/compute/api_scalar.h>
#include <arrow/compute/exec/expression.h>

namespace compute = ::arrow::compute;

std::shared_ptr<compute::FunctionOptions> make_compute_options(std::string func_name,
                                                               cpp11::list options);

// [[arrow::export]]
std::shared_ptr<compute::Expression> compute___expr__call(std::string func_name,
                                                          cpp11::list argument_list,
                                                          cpp11::list options) {
  std::vector<compute::Expression> arguments;
  for (SEXP argument : argument_list) {
    auto argument_ptr = cpp11::as_cpp<std::shared_ptr<compute::Expression>>(argument);
    arguments.push_back(*argument_ptr);
  }

  auto options_ptr = make_compute_options(func_name, options);

  return std::make_shared<compute::Expression>(
      compute::call(std::move(func_name), std::move(arguments), std::move(options_ptr)));
}

// [[arrow::export]]
std::shared_ptr<compute::Expression> compute___expr__field_ref(std::string name) {
  return std::make_shared<compute::Expression>(compute::field_ref(std::move(name)));
}

// [[arrow::export]]
std::string compute___expr__get_field_ref_name(
    const std::shared_ptr<compute::Expression>& x) {
  if (auto field_ref = x->field_ref()) {
    return *field_ref->name();
  }
  return "";
}

// [[arrow::export]]
std::shared_ptr<compute::Expression> compute___expr__scalar(
    const std::shared_ptr<arrow::Scalar>& x) {
  return std::make_shared<compute::Expression>(compute::literal(std::move(x)));
}

// [[arrow::export]]
std::string compute___expr__ToString(const std::shared_ptr<compute::Expression>& x) {
  return x->ToString();
}

#endif