text: /*
   * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
   *
   * Licensed under the Apache License, Version 2.0 (the "License").
   * You may not use this file except in compliance with the License.
   * A copy of the License is located at
   *
   *     http://aws.amazon.com/apache2.0/
   *
   * or in the "license" file accompanying this file. This file 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.
   */
  /*
   * Test expression parsing
   */
  
  #include <chrono>
  
  #include "utils.h"
  
  #include "apl/datagrammar/bytecode.h"
  #include "apl/engine/evaluate.h"
  #include "apl/primitives/symbolreferencemap.h"
  #include "apl/utils/dump_object.h"
  
  static const char *USAGE_STRING = "parseExpression [OPTIONS] EXPRESSION*";
  
  int
  main(int argc, char *argv[])
  {
      ArgumentSet argumentSet(USAGE_STRING);
      ViewportSettings settings(argumentSet);
  
      bool optimize = false;
      long repetitions = 0;
      bool verbose = false;
  
      argumentSet.add({
          Argument("-o",
                   "--optimize",
                   Argument::NONE,
                   "Run the byte code optimizer",
                   "",
                   [&](const std::vector<std::string>&) {
                       optimize = true;
                   }),
          Argument("-n",
                   "--number",
                   Argument::ONE,
                   "Measure performance over multiple repetitions",
                   "REPS",
                   [&](const std::vector<std::string>& value) {
                       repetitions = std::stol(value[0]);
                       if (repetitions < 0)
                           repetitions = 0;
                   }),
          Argument("-v",
                   "--verbose",
                   Argument::NONE,
                   "Verbose",
                   "",
                   [&](const std::vector<std::string>&) {
                       verbose = true;
                   })
      });
  
      std::vector<std::string> args(argv + 1, argv + argc);
      argumentSet.parse(args);
  
      auto c = settings.createContext();
  
      auto now = std::chrono::duration_cast<std::chrono::milliseconds>(
          std::chrono::system_clock::now().time_since_epoch());
      c->putSystemWriteable("utcTime", now.count());
  
      if (repetitions > 0) {
          auto start = std::chrono::high_resolution_clock::now();
  
          for (const auto& m : args) {
              // When the optimize flag is turned on, we optimize the expression once
              // and evaluate it "N" times
              if (optimize) {
                  auto cbc = apl::getDataBinding(*c, m);
                  if (cbc.isByteCode()) {
                      apl::SymbolReferenceMap map;
                      cbc.symbols(map);
                  }
  
                  for (long i = 0 ; i < repetitions ; i++)
                      cbc.eval();
              }
              else {  // When the optimize flag is turned off, we evaluated the expression "N" times.
                  for (long i = 0 ; i < repetitions ; i++)
                      apl::evaluate(*c, m);
              }
          }
  
          auto stop = std::chrono::high_resolution_clock::now();
          auto duration = std::chrono::duration_cast<std::chrono::microseconds>(stop - start);
  
          std::cout << u8"Duration (µs): " << duration.count() << std::endl
                    << u8"Average  (µs): " << (duration.count() / repetitions) << std::endl;
      }
      else {
          for (const auto& m : args) {
              if (verbose)
                  std::cout << "parsing '" << m << "'" << std::endl;
  
              auto cbc = apl::getDataBinding(*c, m);
  
              if (verbose && cbc.isByteCode())
                  cbc.getByteCode()->dump();
  
              std::cout << "Evaluates to " << cbc.eval().asString() << std::endl;
  
              if (optimize && cbc.isByteCode()) {
                  apl::SymbolReferenceMap map;
                  cbc.symbols(map);
                  std::cout << std::endl << "Optimized version" << std::endl;
                  cbc.getByteCode()->dump();
                  std::cout << "optimized version evaluates to " << cbc.eval().asString() << std::endl;
              }
          }
      }
  }
  