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/*

 * 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 <string>

#include <fstream>

#include <iostream>

#include <vector>

#include <stdlib.h>

#include <sys/stat.h>

#include <sys/types.h>

#include <sstream>

#include "t_generator.h"

#include "platform.h"

using namespace std;

/**

 * Erlang code generator.

 *

 */

class t_erl_generator : public t_generator {

 public:

  t_erl_generator(

      t_program* program,

      const std::map<std::string, std::string>& parsed_options,

      const std::string& option_string)

    : t_generator(program)

  {

    program_name_[0] = tolower(program_name_[0]);

    service_name_[0] = tolower(service_name_[0]);

    out_dir_base_ = "gen-erl";

  }

  /**

   * Init and close methods

   */

  void init_generator();

  void close_generator();

  /**

   * Program-level generation functions

   */

  void generate_typedef  (t_typedef*  ttypedef);

  void generate_enum     (t_enum*     tenum);

  void generate_const    (t_const*    tconst);

  void generate_struct   (t_struct*   tstruct);

  void generate_xception (t_struct*   txception);

  void generate_service  (t_service*  tservice);

  std::string render_const_value(t_type* type, t_const_value* value);

  /**

   * Struct generation code

   */

  void generate_erl_struct(t_struct* tstruct, bool is_exception);

  void generate_erl_struct_definition(std::ostream& out, std::ostream& hrl_out, t_struct* tstruct, bool is_xception=false, bool is_result=false);

  void generate_erl_struct_info(std::ostream& out, t_struct* tstruct);

  void generate_erl_function_helpers(t_function* tfunction);

  /**

   * Service-level generation functions

   */

  void generate_service_helpers   (t_service*  tservice);

  void generate_service_interface (t_service* tservice);

  void generate_function_info     (t_service* tservice, t_function* tfunction);

  /**

   * Helper rendering functions

   */

  std::string erl_autogen_comment();

  std::string erl_imports();

  std::string render_includes();

  std::string declare_field(t_field* tfield);

  std::string type_name(t_type* ttype);

  std::string function_signature(t_function* tfunction, std::string prefix="");

  std::string argument_list(t_struct* tstruct);

  std::string type_to_enum(t_type* ttype);

  std::string generate_type_term(t_type* ttype, bool expand_structs);

  std::string type_module(t_type* ttype);

  std::string capitalize(std::string in) {

    in[0] = toupper(in[0]);

    return in;

  }

  std::string uncapitalize(std::string in) {

    in[0] = tolower(in[0]);

    return in;

  }

 private:

  /**

   * add function to export list

   */

  void export_function(t_function* tfunction, std::string prefix="");

  void export_string(std::string name, int num);

  void export_types_function(t_function* tfunction, std::string prefix="");

  void export_types_string(std::string name, int num);

  /**

   * write out headers and footers for hrl files

   */

  void hrl_header(std::ostream& out, std::string name);

  void hrl_footer(std::ostream& out, std::string name);

  /**

   * stuff to spit out at the top of generated files

   */

  bool export_lines_first_;

  std::ostringstream export_lines_;

  bool export_types_lines_first_;

  std::ostringstream export_types_lines_;

  /**

   * File streams

   */

  std::ostringstream f_types_;

  std::ofstream f_types_file_;

  std::ofstream f_types_hrl_file_;

  std::ofstream f_consts_;

  std::ostringstream f_service_;

  std::ofstream f_service_file_;

  std::ofstream f_service_hrl_;

};

/**

 * UI for file generation by opening up the necessary file output

 * streams.

 *

 * @param tprogram The program to generate

 */

void t_erl_generator::init_generator() {

  // Make output directory

  MKDIR(get_out_dir().c_str());

  // setup export lines

  export_lines_first_ = true;

  export_types_lines_first_ = true;

  // types files

  string f_types_name = get_out_dir()+program_name_+"_types.erl";

  string f_types_hrl_name = get_out_dir()+program_name_+"_types.hrl";

  f_types_file_.open(f_types_name.c_str());

  f_types_hrl_file_.open(f_types_hrl_name.c_str());

  hrl_header(f_types_hrl_file_, program_name_ + "_types");

  f_types_file_ <<

    erl_autogen_comment() << endl <<

    "-module(" << program_name_ << "_types)." << endl <<

    erl_imports() << endl;

  f_types_file_ <<

    "-include(\"" << program_name_ << "_types.hrl\")." << endl <<

    endl;

  f_types_hrl_file_ << render_includes() << endl;

  // consts file

  string f_consts_name = get_out_dir()+program_name_+"_constants.hrl";

  f_consts_.open(f_consts_name.c_str());

  f_consts_ <<

    erl_autogen_comment() << endl <<

    erl_imports() << endl <<

    "-include(\"" << program_name_ << "_types.hrl\")." << endl <<

    endl;

}

/**

 * Boilerplate at beginning and end of header files

 */

void t_erl_generator::hrl_header(ostream& out, string name) {

  out << "-ifndef(_" << name << "_included)." << endl <<

    "-define(_" << name << "_included, yeah)." << endl;

}

void t_erl_generator::hrl_footer(ostream& out, string name) {

  out << "-endif." << endl;

}

/**

 * Renders all the imports necessary for including another Thrift program

 */

string t_erl_generator::render_includes() {

  const vector<t_program*>& includes = program_->get_includes();

  string result = "";

  for (size_t i = 0; i < includes.size(); ++i) {

    result += "-include(\"" + uncapitalize(includes[i]->get_name()) + "_types.hrl\").\n";

  }

  if (includes.size() > 0) {

    result += "\n";

  }

  return result;

}

/**

 * Autogen'd comment

 */

string t_erl_generator::erl_autogen_comment() {

  return

    std::string("%%\n") +

    "%% Autogenerated by Thrift\n" +

    "%%\n" +

    "%% DO NOT EDIT UNLESS YOU ARE SURE THAT YOU KNOW WHAT YOU ARE DOING\n" +

    "%%\n";

}

/**

 * Prints standard thrift imports

 */

string t_erl_generator::erl_imports() {

  return "";

}

/**

 * Closes the type files

 */

void t_erl_generator::close_generator() {

  // Close types file

  export_types_string("struct_info", 1);

  f_types_file_ << "-export([" << export_types_lines_.str() << "])." << endl;

  f_types_file_ << f_types_.str();

  f_types_file_ << "struct_info('i am a dummy struct') -> undefined." << endl;

  hrl_footer(f_types_hrl_file_, string("BOGUS"));

  f_types_file_.close();

  f_types_hrl_file_.close();

  f_consts_.close();

}

/**

 * Generates a typedef. no op

 *

 * @param ttypedef The type definition

 */

void t_erl_generator::generate_typedef(t_typedef* ttypedef) {

}

/**

 * Generates code for an enumerated type. Done using a class to scope

 * the values.

 *

 * @param tenum The enumeration

 */

void t_erl_generator::generate_enum(t_enum* tenum) {

  vector<t_enum_value*> constants = tenum->get_constants();

  vector<t_enum_value*>::iterator c_iter;

  int value = -1;

  for (c_iter = constants.begin(); c_iter != constants.end(); ++c_iter) {

    if ((*c_iter)->has_value()) {

      value = (*c_iter)->get_value();

    } else {

      ++value;

    }

    string name = capitalize((*c_iter)->get_name());

    f_types_hrl_file_ <<

      indent() << "-define(" << program_name_ << "_" << name << ", " << value << ")."<< endl;

  }

  f_types_hrl_file_ << endl;

}

/**

 * Generate a constant value

 */

void t_erl_generator::generate_const(t_const* tconst) {

  t_type* type = tconst->get_type();

  string name = capitalize(tconst->get_name());

  t_const_value* value = tconst->get_value();

  f_consts_ << "-define(" << program_name_ << "_" << name << ", " << render_const_value(type, value) << ")." << endl << endl;

}

/**

 * Prints the value of a constant with the given type. Note that type checking

 * is NOT performed in this function as it is always run beforehand using the

 * validate_types method in main.cc

 */

string t_erl_generator::render_const_value(t_type* type, t_const_value* value) {

  type = get_true_type(type);

  std::ostringstream out;

  if (type->is_base_type()) {

    t_base_type::t_base tbase = ((t_base_type*)type)->get_base();

    switch (tbase) {

    case t_base_type::TYPE_STRING:

      out << '"' << get_escaped_string(value) << '"';

      break;

    case t_base_type::TYPE_BOOL:

      out << (value->get_integer() > 0 ? "true" : "false");

      break;

    case t_base_type::TYPE_BYTE:

    case t_base_type::TYPE_I16:

    case t_base_type::TYPE_I32:

    case t_base_type::TYPE_I64:

      out << value->get_integer();

      break;

    case t_base_type::TYPE_DOUBLE:

      if (value->get_type() == t_const_value::CV_INTEGER) {

        out << value->get_integer();

      } else {

        out << value->get_double();

      }

      break;

    default:

      throw "compiler error: no const of base type " + t_base_type::t_base_name(tbase);

    }

  } else if (type->is_enum()) {

    indent(out) << value->get_integer();

  } else if (type->is_struct() || type->is_xception()) {

    out << "#" << type->get_name() << "{";

    const vector<t_field*>& fields = ((t_struct*)type)->get_members();

    vector<t_field*>::const_iterator f_iter;

    const map<t_const_value*, t_const_value*>& val = value->get_map();

    map<t_const_value*, t_const_value*>::const_iterator v_iter;

    bool first = true;

    for (v_iter = val.begin(); v_iter != val.end(); ++v_iter) {

      t_type* field_type = NULL;

      for (f_iter = fields.begin(); f_iter != fields.end(); ++f_iter) {

        if ((*f_iter)->get_name() == v_iter->first->get_string()) {

          field_type = (*f_iter)->get_type();

        }

      }

      if (field_type == NULL) {

        throw "type error: " + type->get_name() + " has no field " + v_iter->first->get_string();

      }

      if (first) {

        first = false;

      } else {

        out << ",";

      }

      out << v_iter->first->get_string();

      out << " = ";

      out << render_const_value(field_type, v_iter->second);

    }

    indent_down();

    indent(out) << "}";

  } else if (type->is_map()) {

    t_type* ktype = ((t_map*)type)->get_key_type();

    t_type* vtype = ((t_map*)type)->get_val_type();

    const map<t_const_value*, t_const_value*>& val = value->get_map();

    map<t_const_value*, t_const_value*>::const_iterator v_iter;

    bool first = true;

    out << "dict:from_list([";

    for (v_iter = val.begin(); v_iter != val.end(); ++v_iter) {

      if (first) {

        first=false;

      } else {

        out << ",";

      }

      out << "("

          << render_const_value(ktype, v_iter->first)  << ","

          << render_const_value(vtype, v_iter->second) << ")";

    }

    out << "])";

  } else if (type->is_set()) {

    t_type* etype;

    etype = ((t_set*)type)->get_elem_type();

    bool first = true;

    const vector<t_const_value*>& val = value->get_list();

    vector<t_const_value*>::const_iterator v_iter;

    out << "sets:from_list([";

    for (v_iter = val.begin(); v_iter != val.end(); ++v_iter) {

      if (first) {

        first=false;

      } else {

        out << ",";

      }

      out << "(" << render_const_value(etype, *v_iter) << ",true)";

    }

    out << "])";

  } else if (type->is_list()) {

    t_type* etype;

    etype = ((t_list*)type)->get_elem_type();

    out << "[";

    bool first = true;

    const vector<t_const_value*>& val = value->get_list();

    vector<t_const_value*>::const_iterator v_iter;

    for (v_iter = val.begin(); v_iter != val.end(); ++v_iter) {

      if (first) {

        first=false;

      } else {

        out << ",";

      }

      out << render_const_value(etype, *v_iter);

    }

    out << "]";

  } else {

    throw "CANNOT GENERATE CONSTANT FOR TYPE: " + type->get_name();

  }

  return out.str();

}

/**

 * Generates a struct

 */

void t_erl_generator::generate_struct(t_struct* tstruct) {

  generate_erl_struct(tstruct, false);

}

/**

 * Generates a struct definition for a thrift exception. Basically the same

 * as a struct but extends the Exception class.

 *

 * @param txception The struct definition

 */

void t_erl_generator::generate_xception(t_struct* txception) {

  generate_erl_struct(txception, true);

}

/**

 * Generates a struct

 */

void t_erl_generator::generate_erl_struct(t_struct* tstruct,

                                          bool is_exception) {

  generate_erl_struct_definition(f_types_, f_types_hrl_file_, tstruct, is_exception);

}

/**

 * Generates a struct definition for a thrift data type.

 *

 * @param tstruct The struct definition

 */

void t_erl_generator::generate_erl_struct_definition(ostream& out,

                                                     ostream& hrl_out,

                                                     t_struct* tstruct,

                                                     bool is_exception,

                                                     bool is_result)

{

  const vector<t_field*>& members = tstruct->get_members();

  vector<t_field*>::const_iterator m_iter;

  indent(out) << "%% struct " << type_name(tstruct) << endl;

  if (is_exception) {

  }

  out << endl;

  if (members.size() > 0) {

    indent(out)     << "% -record(" << type_name(tstruct) << ", {";

    indent(hrl_out) <<   "-record(" << type_name(tstruct) << ", {";

    bool first = true;

    for (m_iter = members.begin(); m_iter != members.end(); ++m_iter) {

      if (first) {

        first = false;

      } else {

        out     << ", ";

        hrl_out << ", ";

      }

      std::string name = uncapitalize((*m_iter)->get_name());

      out     << name;

      hrl_out << name;

    }

    out     << "})." << endl;

    hrl_out << "})." << endl;

  } else { // no members; explicit comment

    indent(out)     << "% -record(" << type_name(tstruct) << ", {})." << endl;

    indent(hrl_out) <<   "-record(" << type_name(tstruct) << ", {})." << endl;

  }

  out << endl;

  hrl_out << endl;

  generate_erl_struct_info(out, tstruct);

}

/**

 * Generates the read method for a struct

 */

void t_erl_generator::generate_erl_struct_info(ostream& out,

                                                  t_struct* tstruct) {

  string name = type_name(tstruct);

  indent(out) << "struct_info('" << name << "') ->" << endl;

  indent_up();

  out << indent() << generate_type_term(tstruct, true) << ";" << endl;

  indent_down();

  out << endl;

}

/**

 * Generates a thrift service.

 *

 * @param tservice The service definition

 */

void t_erl_generator::generate_service(t_service* tservice) {

  // somehow this point is reached before the constructor and it's not downcased yet

  // ...awesome

  service_name_[0] = tolower(service_name_[0]);

  string f_service_hrl_name = get_out_dir()+service_name_+"_thrift.hrl";

  string f_service_name = get_out_dir()+service_name_+"_thrift.erl";

  f_service_file_.open(f_service_name.c_str());

  f_service_hrl_.open(f_service_hrl_name.c_str());

  // Reset service text aggregating stream streams

  f_service_.str("");

  export_lines_.str("");

  export_lines_first_ = true;

  hrl_header(f_service_hrl_, service_name_);

  if (tservice->get_extends() != NULL) {

    f_service_hrl_ << "-include(\"" <<

      uncapitalize(tservice->get_extends()->get_name()) << "_thrift.hrl\"). % inherit " << endl;

  }

  f_service_hrl_ <<

    "-include(\"" << program_name_ << "_types.hrl\")." << endl <<

    endl;

  // Generate the three main parts of the service (well, two for now in PHP)

  generate_service_helpers(tservice); // cpiro: New Erlang Order

  generate_service_interface(tservice);

  // indent_down();

  f_service_file_ <<

    erl_autogen_comment() << endl <<

    "-module(" << service_name_ << "_thrift)." << endl <<

    "-behaviour(thrift_service)." << endl << endl <<

    erl_imports() << endl;

  f_service_file_ << "-include(\"" << uncapitalize(tservice->get_name()) << "_thrift.hrl\")." << endl << endl;

  f_service_file_ << "-export([" << export_lines_.str() << "])." << endl << endl;

  f_service_file_ << f_service_.str();

  hrl_footer(f_service_hrl_, f_service_name);

  // Close service file

  f_service_file_.close();

  f_service_hrl_.close();

}

/**

 * Generates helper functions for a service.

 *

 * @param tservice The service to generate a header definition for

 */

void t_erl_generator::generate_service_helpers(t_service* tservice) {

  vector<t_function*> functions = tservice->get_functions();

  vector<t_function*>::iterator f_iter;

  //  indent(f_service_) <<

  //  "% HELPER FUNCTIONS AND STRUCTURES" << endl << endl;

  export_string("struct_info", 1);

  for (f_iter = functions.begin(); f_iter != functions.end(); ++f_iter) {

    generate_erl_function_helpers(*f_iter);

  }

  f_service_    << "struct_info('i am a dummy struct') -> undefined." << endl;

}

/**

 * Generates a struct and helpers for a function.

 *

 * @param tfunction The function

 */

void t_erl_generator::generate_erl_function_helpers(t_function* tfunction) {

}

/**

 * Generates a service interface definition.

 *

 * @param tservice The service to generate a header definition for

 */

void t_erl_generator::generate_service_interface(t_service* tservice) {

  export_string("function_info", 2);

  vector<t_function*> functions = tservice->get_functions();

  vector<t_function*>::iterator f_iter;

  f_service_ << "%%% interface" << endl;

  for (f_iter = functions.begin(); f_iter != functions.end(); ++f_iter) {

    f_service_ <<

      indent() << "% " << function_signature(*f_iter) << endl;

    generate_function_info(tservice, *f_iter);

  }

  // Inheritance - pass unknown functions to base class

  if (tservice->get_extends() != NULL) {

      indent(f_service_) << "function_info(Function, InfoType) ->" << endl;

      indent_up();

      indent(f_service_) << uncapitalize(tservice->get_extends()->get_name())

                         << "_thrift:function_info(Function, InfoType)." << endl;

      indent_down();

  } else {

      // Dummy function_info so we don't worry about the ;s

      indent(f_service_) << "function_info(xxx, dummy) -> dummy." << endl;

  }

  indent(f_service_) << endl;

}

/**

 * Generates a function_info(FunctionName, params_type) and

 * function_info(FunctionName, reply_type)

 */

void t_erl_generator::generate_function_info(t_service* tservice,

                                                t_function* tfunction) {

  string name_atom = "'" + tfunction->get_name() + "'";

  t_struct* xs = tfunction->get_xceptions();

  t_struct* arg_struct = tfunction->get_arglist();

  // function_info(Function, params_type):

  indent(f_service_) <<

    "function_info(" << name_atom << ", params_type) ->" << endl;

  indent_up();

  indent(f_service_) << generate_type_term(arg_struct, true) << ";" << endl;

  indent_down();

  // function_info(Function, reply_type):

  indent(f_service_) <<

    "function_info(" << name_atom << ", reply_type) ->" << endl;

  indent_up();

  if (!tfunction->get_returntype()->is_void())

    indent(f_service_) <<

        generate_type_term(tfunction->get_returntype(), false) << ";" << endl;

  else if (tfunction->is_oneway())

    indent(f_service_) << "oneway_void;" << endl;

  else

    indent(f_service_) << "{struct, []}" << ";" << endl;

  indent_down();

  // function_info(Function, exceptions):

  indent(f_service_) <<

    "function_info(" << name_atom << ", exceptions) ->" << endl;

  indent_up();

  indent(f_service_) << generate_type_term(xs, true) << ";" << endl;

  indent_down();

}

/**

 * Declares a field, which may include initialization as necessary.

 *

 * @param ttype The type

 */

string t_erl_generator::declare_field(t_field* tfield) {  // TODO

  string result = "@" + tfield->get_name();

  t_type* type = get_true_type(tfield->get_type());

  if (tfield->get_value() != NULL) {

    result += " = " + render_const_value(type, tfield->get_value());

  } else {

    result += " = nil";

  }

  return result;

}

/**

 * Renders a function signature of the form 'type name(args)'

 *

 * @param tfunction Function definition

 * @return String of rendered function definition

 */

string t_erl_generator::function_signature(t_function* tfunction,

                                           string prefix) {

  return

    prefix + tfunction->get_name() +

    "(This" +  capitalize(argument_list(tfunction->get_arglist())) + ")";

}

/**

 * Add a function to the exports list

 */

void t_erl_generator::export_string(string name, int num) {

  if (export_lines_first_) {

    export_lines_first_ = false;

  } else {

    export_lines_ << ", ";

  }

  export_lines_ << name << "/" << num;

}

void t_erl_generator::export_types_function(t_function* tfunction,

                                               string prefix) {

  export_types_string(prefix + tfunction->get_name(),

                      1 // This

                      + ((tfunction->get_arglist())->get_members()).size()

                      );

}

void t_erl_generator::export_types_string(string name, int num) {

  if (export_types_lines_first_) {

    export_types_lines_first_ = false;

  } else {

    export_types_lines_ << ", ";

  }

  export_types_lines_ << name << "/" << num;

}

void t_erl_generator::export_function(t_function* tfunction,

                                      string prefix) {

  export_string(prefix + tfunction->get_name(),

                1 // This

                + ((tfunction->get_arglist())->get_members()).size()

                );

}

/**

 * Renders a field list

 */

string t_erl_generator::argument_list(t_struct* tstruct) {

  string result = "";

  const vector<t_field*>& fields = tstruct->get_members();

  vector<t_field*>::const_iterator f_iter;

  bool first = true;

  for (f_iter = fields.begin(); f_iter != fields.end(); ++f_iter) {

    if (first) {

      first = false;

      result += ", "; // initial comma to compensate for initial This

    } else {

      result += ", ";

    }

    result += capitalize((*f_iter)->get_name());

  }

  return result;

}

string t_erl_generator::type_name(t_type* ttype) {

  string prefix = "";

  string name = ttype->get_name();

  if (ttype->is_struct() || ttype->is_xception() || ttype->is_service()) {

    name = uncapitalize(ttype->get_name());

  }

  return prefix + name;

}

/**

 * Converts the parse type to a Erlang "type" (macro for int constants)

 */

string t_erl_generator::type_to_enum(t_type* type) {

  type = get_true_type(type);

  if (type->is_base_type()) {

    t_base_type::t_base tbase = ((t_base_type*)type)->get_base();

    switch (tbase) {

    case t_base_type::TYPE_VOID:

      throw "NO T_VOID CONSTRUCT";

    case t_base_type::TYPE_STRING:

      return "?tType_STRING";

    case t_base_type::TYPE_BOOL:

      return "?tType_BOOL";

    case t_base_type::TYPE_BYTE:

      return "?tType_BYTE";

    case t_base_type::TYPE_I16:

      return "?tType_I16";

    case t_base_type::TYPE_I32:

      return "?tType_I32";

    case t_base_type::TYPE_I64:

      return "?tType_I64";

    case t_base_type::TYPE_DOUBLE:

      return "?tType_DOUBLE";

    }

  } else if (type->is_enum()) {

    return "?tType_I32";

  } else if (type->is_struct() || type->is_xception()) {

    return "?tType_STRUCT";

  } else if (type->is_map()) {

    return "?tType_MAP";

  } else if (type->is_set()) {

    return "?tType_SET";

  } else if (type->is_list()) {

    return "?tType_LIST";

  }

  throw "INVALID TYPE IN type_to_enum: " + type->get_name();

}

/**

 * Generate an Erlang term which represents a thrift type

 */

std::string t_erl_generator::generate_type_term(t_type* type,

                                                   bool expand_structs) {

    type = get_true_type(type);

  if (type->is_base_type()) {

    t_base_type::t_base tbase = ((t_base_type*)type)->get_base();

    switch (tbase) {

    case t_base_type::TYPE_VOID:

      throw "NO T_VOID CONSTRUCT";

    case t_base_type::TYPE_STRING:

      return "string";

    case t_base_type::TYPE_BOOL:

      return "bool";

    case t_base_type::TYPE_BYTE:

      return "byte";

    case t_base_type::TYPE_I16:

      return "i16";

    case t_base_type::TYPE_I32:

      return "i32";

    case t_base_type::TYPE_I64:

      return "i64";

    case t_base_type::TYPE_DOUBLE:

      return "double";

    }

  } else if (type->is_enum()) {

    return "i32";

  } else if (type->is_struct() || type->is_xception()) {

    if (expand_structs) {

      // Convert to format: {struct, [{Fid, TypeTerm}, {Fid, TypeTerm}...]}

      std::stringstream ret;

      ret << "{struct, [";

      int first = true;

      const vector<t_field*>& fields = ((t_struct*)type)->get_members();

      vector<t_field*>::const_iterator f_iter;

      for (f_iter = fields.begin(); f_iter != fields.end(); ++f_iter) {

        // Comma separate the tuples

        if (!first) ret << "," << endl << indent();

        first = false;

        ret << "{" << (*f_iter)->get_key() << ", " <<

          generate_type_term((*f_iter)->get_type(), false) << "}";

      }

      ret << "]}" << endl;

      return ret.str();

    } else {

      return "{struct, {'" + type_module(type) + "', '" + type_name(type) + "'}}";

    }

  } else if (type->is_map()) {

    // {map, KeyType, ValType}

    t_type *key_type = ((t_map*)type)->get_key_type();

    t_type *val_type = ((t_map*)type)->get_val_type();

    return "{map, " + generate_type_term(key_type, false) + ", " +

      generate_type_term(val_type, false) + "}";

  } else if (type->is_set()) {

    t_type *elem_type = ((t_set*)type)->get_elem_type();

    return "{set, " + generate_type_term(elem_type, false) + "}";

  } else if (type->is_list()) {

    t_type *elem_type = ((t_list*)type)->get_elem_type();

    return "{list, " + generate_type_term(elem_type, false) + "}";

  }

  throw "INVALID TYPE IN type_to_enum: " + type->get_name();

}

std::string t_erl_generator::type_module(t_type* ttype) {

  return uncapitalize(ttype->get_program()->get_name()) + "_types";

}

THRIFT_REGISTER_GENERATOR(erl, "Erlang", "");