text: #ifndef STAN_LANG_GENERATOR_GENERATE_USINGS_STANDALONE_FUNCTIONS_HPP
  #define STAN_LANG_GENERATOR_GENERATE_USINGS_STANDALONE_FUNCTIONS_HPP
  
  #include "constants.hpp"
  #include "generate_using.hpp"
  #include "generate_using_namespace.hpp"
  #include "stan/language/ast.hpp"
  #include <ostream>
  
  namespace stan {
  namespace lang {
  
  /**
   * Generate the using statements for a Stan standalone functions file.
   *
   * @param[in,out] o stream for generating
   */
  void generate_usings_standalone_functions(std::ostream& o) {
    generate_using("std::istream", o);
    generate_using("std::string", o);
    generate_using("std::stringstream", o);
    generate_using("std::vector", o);
    generate_using_namespace("stan::math", o);
    o << EOL;
  }
  
  }  // namespace lang
  }  // namespace stan
  #endif
  