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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_oop_generator.h"

#include "platform.h"

using namespace std;

/**

 * OCaml code generator.

 *

 */

class t_ocaml_generator : public t_oop_generator {

 public:

  t_ocaml_generator(

      t_program* program,

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

      const std::string& option_string)

    : t_oop_generator(program)

  {

    out_dir_base_ = "gen-ocaml";

  }

  /**

   * Init and close methods

   */

  void init_generator();

  void close_generator();

  /**

   * Program-level generation functions

   */

  void generate_program  ();

  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_ocaml_struct(t_struct* tstruct, bool is_exception);

  void generate_ocaml_struct_definition(std::ofstream& out, t_struct* tstruct, bool is_xception=false);

  void generate_ocaml_struct_sig(std::ofstream& out, t_struct* tstruct, bool is_exception);

  void generate_ocaml_struct_reader(std::ofstream& out, t_struct* tstruct);

  void generate_ocaml_struct_writer(std::ofstream& out, t_struct* tstruct);

  void generate_ocaml_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_service_client    (t_service* tservice);

  void generate_service_server    (t_service* tservice);

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

  /**

   * Serialization constructs

   */

  void generate_deserialize_field        (std::ofstream &out,

                                          t_field*    tfield,

                                          std::string prefix);

  void generate_deserialize_struct       (std::ofstream &out,

                                          t_struct*   tstruct);

  void generate_deserialize_container    (std::ofstream &out,

                                          t_type*     ttype);

  void generate_deserialize_set_element  (std::ofstream &out,

                                          t_set*      tset);

  void generate_deserialize_list_element (std::ofstream &out,

                                          t_list*     tlist,

                                          std::string prefix="");

  void generate_deserialize_type          (std::ofstream &out,

                                           t_type* type);

  void generate_serialize_field          (std::ofstream &out,

                                          t_field*    tfield,

                                          std::string name= "");

  void generate_serialize_struct         (std::ofstream &out,

                                          t_struct*   tstruct,

                                          std::string prefix="");

  void generate_serialize_container      (std::ofstream &out,

                                          t_type*     ttype,

                                          std::string prefix="");

  void generate_serialize_map_element    (std::ofstream &out,

                                          t_map*      tmap,

                                          std::string kiter,

                                          std::string viter);

  void generate_serialize_set_element    (std::ofstream &out,

                                          t_set*      tmap,

                                          std::string iter);

  void generate_serialize_list_element   (std::ofstream &out,

                                          t_list*     tlist,

                                          std::string iter);

  /**

   * Helper rendering functions

   */

  std::string ocaml_autogen_comment();

  std::string ocaml_imports();

  std::string type_name(t_type* ttype);

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

  std::string function_type(t_function* tfunc, bool method=false, bool options = false);

  std::string argument_list(t_struct* tstruct);

  std::string type_to_enum(t_type* ttype);

  std::string render_ocaml_type(t_type* type);

 private:

  /**

   * File streams

   */

  std::ofstream f_types_;

  std::ofstream f_consts_;

  std::ofstream f_service_;

  std::ofstream f_types_i_;

  std::ofstream f_service_i_;

};

/*

 * This is necessary because we want typedefs to appear later,

 * after all the types have been declared.

 */

void t_ocaml_generator::generate_program() {

  // Initialize the generator

  init_generator();

  // Generate enums

  vector<t_enum*> enums = program_->get_enums();

  vector<t_enum*>::iterator en_iter;

  for (en_iter = enums.begin(); en_iter != enums.end(); ++en_iter) {

    generate_enum(*en_iter);

  }

  // Generate structs

  vector<t_struct*> structs = program_->get_structs();

  vector<t_struct*>::iterator st_iter;

  for (st_iter = structs.begin(); st_iter != structs.end(); ++st_iter) {

    generate_struct(*st_iter);

  }

  // Generate xceptions

  vector<t_struct*> xceptions = program_->get_xceptions();

  vector<t_struct*>::iterator x_iter;

  for (x_iter = xceptions.begin(); x_iter != xceptions.end(); ++x_iter) {

    generate_xception(*x_iter);

  }

  // Generate typedefs

  vector<t_typedef*> typedefs = program_->get_typedefs();

  vector<t_typedef*>::iterator td_iter;

  for (td_iter = typedefs.begin(); td_iter != typedefs.end(); ++td_iter) {

    generate_typedef(*td_iter);

  }

  // Generate services

  vector<t_service*> services = program_->get_services();

  vector<t_service*>::iterator sv_iter;

  for (sv_iter = services.begin(); sv_iter != services.end(); ++sv_iter) {

    service_name_ = get_service_name(*sv_iter);

    generate_service(*sv_iter);

  }

  // Generate constants

  vector<t_const*> consts = program_->get_consts();

  generate_consts(consts);

  // Close the generator

  close_generator();

}

/**

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

 * streams.

 *

 * @param tprogram The program to generate

 */

void t_ocaml_generator::init_generator() {

  // Make output directory

  MKDIR(get_out_dir().c_str());

  // Make output file

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

  f_types_.open(f_types_name.c_str());

  string f_types_i_name = get_out_dir()+program_name_+"_types.mli";

  f_types_i_.open(f_types_i_name.c_str());

  string f_consts_name = get_out_dir()+program_name_+"_consts.ml";

  f_consts_.open(f_consts_name.c_str());

  // Print header

  f_types_ <<

    ocaml_autogen_comment() << endl <<

    ocaml_imports() << endl;

  f_types_i_ <<

    ocaml_autogen_comment() << endl <<

    ocaml_imports() << endl;

  f_consts_ <<

    ocaml_autogen_comment() << endl <<

    ocaml_imports() << endl <<

    "open " << capitalize(program_name_)<<"_types"<< endl;

}

/**

 * Autogen'd comment

 */

string t_ocaml_generator::ocaml_autogen_comment() {

  return

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

    " Autogenerated by Thrift\n" +

    "\n" +

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

    "*)\n";

}

/**

 * Prints standard thrift imports

 */

string t_ocaml_generator::ocaml_imports() {

  return "open Thrift";

}

/**

 * Closes the type files

 */

void t_ocaml_generator::close_generator() {

  // Close types file

  f_types_.close();

}

/**

 * Generates a typedef. Ez.

 *

 * @param ttypedef The type definition

 */

void t_ocaml_generator::generate_typedef(t_typedef* ttypedef) {

  f_types_ <<

    indent() << "type "<< decapitalize(ttypedef->get_symbolic()) << " = " << render_ocaml_type(ttypedef->get_type()) << endl << endl;

  f_types_i_ <<

    indent() << "type "<< decapitalize(ttypedef->get_symbolic()) << " = " << render_ocaml_type(ttypedef->get_type()) << endl << endl;

}

/**

 * Generates code for an enumerated type.

 * the values.

 *

 * @param tenum The enumeration

 */

void t_ocaml_generator::generate_enum(t_enum* tenum) {

  indent(f_types_) << "module " << capitalize(tenum->get_name()) << " = " << endl << "struct" << endl;

  indent(f_types_i_) << "module " << capitalize(tenum->get_name()) << " : " << endl << "sig" << endl;

  indent_up();

  indent(f_types_) << "type t = " << endl;

  indent(f_types_i_) << "type t = " << endl;

  indent_up();

  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) {

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

    indent(f_types_) << "| " << name << endl;

    indent(f_types_i_) << "| " << name << endl;

  }

  indent_down();

  indent(f_types_) << "let to_i = function" << endl;

  indent(f_types_i_) << "val to_i : t -> int" << endl;

  indent_up();

  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_ <<

      indent() << "| " << name << " -> " << value << endl;

  }

  indent_down();

  indent(f_types_) << "let of_i = function" << endl;

  indent(f_types_i_) << "val of_i : int -> t" << endl;

  indent_up();

  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_ <<

      indent() << "| " << value << " -> " << name << endl;

  }

  indent(f_types_) << "| _ -> raise Thrift_error" << endl;

  indent_down();

  indent_down();

  indent(f_types_) << "end" << endl;

  indent(f_types_i_) << "end" << endl;

}

/**

 * Generate a constant value

 */

void t_ocaml_generator::generate_const(t_const* tconst) {

  t_type* type = tconst->get_type();

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

  t_const_value* value = tconst->get_value();

  indent(f_consts_) << "let " << 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_ocaml_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:

      out << value->get_integer();

      break;

    case t_base_type::TYPE_I64:

      out << value->get_integer() << "L";

      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()) {

    t_enum* tenum = (t_enum*)type;

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

    vector<t_enum_value*>::iterator c_iter;

    int val = -1;

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

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

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

      } else {

        ++val;

      }

      if(val == value->get_integer()){

        indent(out) << capitalize(tenum->get_name()) << "." << capitalize((*c_iter)->get_name());

        break;

      }

    }

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

    string cname = type_name(type);

    string ct = tmp("_c");

    out << endl;

    indent_up();

    indent(out) << "(let " << ct << " = new " << cname << " in" << endl;

    indent_up();

    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;

    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();

      }

      string fname = v_iter->first->get_string();

      out << indent();

      out << ct <<"#set_" << fname << " ";

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

      out << ";" << endl;

    }

    indent(out) << ct << ")";

    indent_down();

    indent_down();

  } 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;

    string hm = tmp("_hm");

    out << endl;

    indent_up();

    indent(out) << "(let " << hm << " = Hashtbl.create " << val.size() << " in" << endl;

    indent_up();

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

      string key = render_const_value(ktype, v_iter->first);

      string val = render_const_value(vtype, v_iter->second);

      indent(out) << "Hashtbl.add " << hm << " " << key << " " << val << ";" << endl;

    }

    indent(out) << hm << ")";

    indent_down();

    indent_down();

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

    t_type* etype;

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

    out << "[" << endl;

    indent_up();

    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) {

      out << indent();

      out << render_const_value(etype, *v_iter);

      out << ";" << endl;

    }

    indent_down();

    indent(out) << "]";

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

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

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

    vector<t_const_value*>::const_iterator v_iter;

    string hm = tmp("_hm");

    indent(out) << "(let " << hm << " = Hashtbl.create " << val.size() << " in" << endl;

    indent_up();

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

      string val = render_const_value(etype, *v_iter);

      indent(out) << "Hashtbl.add " << hm << " " << val << " true;" << endl;

    }

    indent(out) << hm << ")" << endl;

    indent_down();

    out << endl;

  } else {

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

  }

  return out.str();

}

/**

 * Generates a "struct"

 */

void t_ocaml_generator::generate_struct(t_struct* tstruct) {

  generate_ocaml_struct(tstruct, false);

}

/**

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

 * as a struct, but also has an exception declaration.

 *

 * @param txception The struct definition

 */

void t_ocaml_generator::generate_xception(t_struct* txception) {

  generate_ocaml_struct(txception, true);

}

/**

 * Generates an OCaml struct

 */

void t_ocaml_generator::generate_ocaml_struct(t_struct* tstruct,

                                              bool is_exception) {

  generate_ocaml_struct_definition(f_types_, tstruct, is_exception);

  generate_ocaml_struct_sig(f_types_i_,tstruct,is_exception);

}

/**

 * Generates a struct definition for a thrift data type.

 *

 * @param tstruct The struct definition

 */

void t_ocaml_generator::generate_ocaml_struct_definition(ofstream& out,

                                                         t_struct* tstruct,

                                                         bool is_exception) {

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

  vector<t_field*>::const_iterator m_iter;

  string tname = type_name(tstruct);

  indent(out) << "class " << tname << " =" << endl;

  indent(out) << "object (self)" << endl;

  indent_up();

  string x = tmp("_x");

  if (members.size() > 0) {

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

      string mname = decapitalize((*m_iter)->get_name());

      indent(out) << "val mutable _" << mname << " : " << render_ocaml_type((*m_iter)->get_type()) << " option = None" << endl;

      indent(out) << "method get_" << mname << " = _" << mname << endl;

      indent(out) << "method grab_" << mname << " = match _"<<mname<<" with None->raise (Field_empty \""<<tname<<"."<<mname<<"\") | Some " << x <<" -> " << x << endl;

      indent(out) << "method set_" << mname << " " << x << " = _" << mname << " <- Some " << x << endl;

    }

  }

  generate_ocaml_struct_writer(out, tstruct);

  indent_down();

  indent(out) << "end" << endl;

  if(is_exception){

    indent(out) << "exception " << capitalize(tname) <<" of " << tname << endl;

  }

  generate_ocaml_struct_reader(out, tstruct);

}

/**

 * Generates a struct definition for a thrift data type.

 *

 * @param tstruct The struct definition

 */

void t_ocaml_generator::generate_ocaml_struct_sig(ofstream& out,

                                                  t_struct* tstruct,

                                                  bool is_exception) {

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

  vector<t_field*>::const_iterator m_iter;

  string tname = type_name(tstruct);

  indent(out) << "class " << tname << " :" << endl;

  indent(out) << "object" << endl;

  indent_up();

  string x = tmp("_x");

  if (members.size() > 0) {

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

      string mname = decapitalize((*m_iter)->get_name());

      string type = render_ocaml_type((*m_iter)->get_type());

      indent(out) << "method get_" << mname << " : " << type << " option" << endl;

      indent(out) << "method grab_" << mname << " : " << type << endl;

      indent(out) << "method set_" << mname << " : " << type << " -> unit" << endl;

    }

  }

  indent(out) << "method write : Protocol.t -> unit" << endl;

  indent_down();

  indent(out) << "end" << endl;

  if(is_exception){

    indent(out) << "exception " << capitalize(tname) <<" of " << tname << endl;

  }

  indent(out) << "val read_" << tname << " : Protocol.t -> " << tname << endl;

}

/**

 * Generates the read method for a struct

 */

void t_ocaml_generator::generate_ocaml_struct_reader(ofstream& out, t_struct* tstruct) {

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

  vector<t_field*>::const_iterator f_iter;

  string sname = type_name(tstruct);

  string str = tmp("_str");

  string t = tmp("_t");

  string id = tmp("_id");

  indent(out) <<

    "let rec read_" << sname << " (iprot : Protocol.t) =" << endl;

  indent_up();

  indent(out) << "let " << str << " = new " << sname << " in" << endl;

  indent_up();

  indent(out) <<

    "ignore(iprot#readStructBegin);" << endl;

  // Loop over reading in fields

  indent(out) <<

    "(try while true do" << endl;

  indent_up();

  indent_up();

  // Read beginning field marker

  indent(out) <<

    "let (_," << t <<","<<id<<") = iprot#readFieldBegin in" << endl;

  // Check for field STOP marker and break

  indent(out) <<

    "if " << t <<" = Protocol.T_STOP then" << endl;

  indent_up();

  indent(out) <<

      "raise Break" << endl;

    indent_down();

    indent(out) << "else ();" << endl;

    indent(out) << "(match " << id<<" with " << endl;

    indent_up();

    // Generate deserialization code for known cases

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

      indent(out) << "| " << (*f_iter)->get_key() << " -> (";

      out << "if " << t <<" = " << type_to_enum((*f_iter)->get_type()) << " then" << endl;

      indent_up();

      indent_up();

      generate_deserialize_field(out, *f_iter,str);

      indent_down();

      out <<

        indent() << "else" << endl <<

        indent() << "  iprot#skip "<< t << ")" << endl;

      indent_down();

    }

    // In the default case we skip the field

    out <<

      indent() << "| _ -> " << "iprot#skip "<<t<<");" << endl;

    indent_down();

    // Read field end marker

    indent(out) << "iprot#readFieldEnd;" << endl;

    indent_down();

    indent(out) << "done; ()" << endl;

    indent_down();

    indent(out) << "with Break -> ());" << endl;

    indent(out) <<

      "iprot#readStructEnd;" << endl;

    indent(out) << str << endl << endl;

    indent_down();

    indent_down();

}

void t_ocaml_generator::generate_ocaml_struct_writer(ofstream& out,

                                               t_struct* tstruct) {

  string name = tstruct->get_name();

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

  vector<t_field*>::const_iterator f_iter;

  string str = tmp("_str");

  string f = tmp("_f");

  indent(out) <<

    "method write (oprot : Protocol.t) =" << endl;

  indent_up();

  indent(out) <<

    "oprot#writeStructBegin \""<<name<<"\";" << endl;

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

    // Write field header

    string mname = "_"+decapitalize((*f_iter)->get_name());

    indent(out) <<

      "(match " << mname << " with None -> () | Some _v -> " << endl;

    indent_up();

    indent(out) << "oprot#writeFieldBegin(\""<< (*f_iter)->get_name()<<"\","

                <<type_to_enum((*f_iter)->get_type())<<","

                <<(*f_iter)->get_key()<<");" << endl;

    // Write field contents

    generate_serialize_field(out, *f_iter, "_v");

    // Write field closer

    indent(out) << "oprot#writeFieldEnd" << endl;

    indent_down();

    indent(out) << ");" << endl;

  }

  // Write the struct map

  out <<

    indent() << "oprot#writeFieldStop;" << endl <<

    indent() << "oprot#writeStructEnd" << endl;

  indent_down();

}

/**

 * Generates a thrift service.

 *

 * @param tservice The service definition

 */

void t_ocaml_generator::generate_service(t_service* tservice) {

  string f_service_name = get_out_dir()+capitalize(service_name_)+".ml";

  f_service_.open(f_service_name.c_str());

  string f_service_i_name = get_out_dir()+capitalize(service_name_)+".mli";

  f_service_i_.open(f_service_i_name.c_str());

  f_service_ <<

    ocaml_autogen_comment() << endl <<

    ocaml_imports() << endl;

  f_service_i_ <<

    ocaml_autogen_comment() << endl <<

    ocaml_imports() << endl;

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

    f_service_ <<

      "open " << capitalize(tservice->get_extends()->get_name()) << endl;

    f_service_i_ <<

      "open " << capitalize(tservice->get_extends()->get_name()) << endl;

  }

  */

  f_service_ <<

     "open " << capitalize(program_name_) << "_types" << endl <<

    endl;

  f_service_i_ <<

     "open " << capitalize(program_name_) << "_types" << endl <<

    endl;

  // Generate the three main parts of the service

  generate_service_helpers(tservice);

  generate_service_interface(tservice);

  generate_service_client(tservice);

  generate_service_server(tservice);

  // Close service file

  f_service_.close();

  f_service_i_.close();

}

/**

 * Generates helper functions for a service.

 *

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

 */

void t_ocaml_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;

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

    t_struct* ts = (*f_iter)->get_arglist();

    generate_ocaml_struct_definition(f_service_, ts, false);

    generate_ocaml_function_helpers(*f_iter);

  }

}

/**

 * Generates a struct and helpers for a function.

 *

 * @param tfunction The function

 */

void t_ocaml_generator::generate_ocaml_function_helpers(t_function* tfunction) {

  t_struct result(program_, decapitalize(tfunction->get_name()) + "_result");

  t_field success(tfunction->get_returntype(), "success", 0);

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

    result.append(&success);

  }

  t_struct* xs = tfunction->get_xceptions();

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

  vector<t_field*>::const_iterator f_iter;

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

    result.append(*f_iter);

  }

  generate_ocaml_struct_definition(f_service_, &result, false);

}

/**

 * Generates a service interface definition.

 *

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

 */

void t_ocaml_generator::generate_service_interface(t_service* tservice) {

  f_service_ <<

    indent() << "class virtual iface =" << endl << "object (self)" << endl;

  f_service_i_ <<

    indent() << "class virtual iface :" << endl << "object" << endl;

  indent_up();

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

    string extends = type_name(tservice->get_extends());

    indent(f_service_) << "inherit " << extends << ".iface" << endl;

    indent(f_service_i_) << "inherit " << extends << ".iface" << endl;

  }

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

  vector<t_function*>::iterator f_iter;

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

    string ft = function_type(*f_iter,true,true);

    f_service_ <<

      indent() << "method virtual " << decapitalize((*f_iter)->get_name()) << " : " << ft  << endl;

    f_service_i_ <<

      indent() << "method virtual " << decapitalize((*f_iter)->get_name()) << " : " << ft << endl;

  }

  indent_down();

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

  indent(f_service_i_) << "end" << endl << endl;

}

/**

 * Generates a service client definition. Note that in OCaml, the client doesn't implement iface. This is because

 * The client does not (and should not have to) deal with arguments being None.

 *

 * @param tservice The service to generate a server for.

 */

void t_ocaml_generator::generate_service_client(t_service* tservice) {

  string extends = "";

  indent(f_service_) <<

    "class client (iprot : Protocol.t) (oprot : Protocol.t) =" << endl << "object (self)" << endl;

  indent(f_service_i_) <<

    "class client : Protocol.t -> Protocol.t -> " << endl << "object" << endl;

  indent_up();

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

    extends = type_name(tservice->get_extends());

    indent(f_service_) << "inherit " << extends << ".client iprot oprot as super" << endl;

    indent(f_service_i_) << "inherit " << extends << ".client" << endl;

  }

  indent(f_service_) << "val mutable seqid = 0" << endl;

  // Generate client method implementations

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

  vector<t_function*>::const_iterator f_iter;

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

    t_struct* arg_struct = (*f_iter)->get_arglist();

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

    vector<t_field*>::const_iterator fld_iter;

    string funname = (*f_iter)->get_name();

    // Open function

    indent(f_service_) <<

      "method " << function_signature(*f_iter) << " = " << endl;

    indent(f_service_i_) <<

      "method " << decapitalize((*f_iter)->get_name()) << " : " << function_type(*f_iter,true,false) << endl;

    indent_up();

    indent(f_service_) <<

      "self#send_" << funname;

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

      f_service_ << " " << decapitalize((*fld_iter)->get_name());

    }

    f_service_ << ";" << endl;

    if (!(*f_iter)->is_oneway()) {

      f_service_ << indent();

      f_service_ <<

        "self#recv_" << funname << endl;

    }

    indent_down();

    indent(f_service_) <<

      "method private send_" << function_signature(*f_iter) << " = " << endl;

    indent_up();

    std::string argsname = decapitalize((*f_iter)->get_name() + "_args");

    // Serialize the request header

    f_service_ <<

      indent() << "oprot#writeMessageBegin (\"" << (*f_iter)->get_name() << "\", Protocol.CALL, seqid);" << endl;

    f_service_ <<

      indent() << "let args = new " << argsname << " in" << endl;

    indent_up();

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

      f_service_ <<

        indent() << "args#set_" << (*fld_iter)->get_name() << " " << (*fld_iter)->get_name() << ";" << endl;

    }

    // Write to the stream

    f_service_ <<

      indent() << "args#write oprot;" << endl <<

      indent() << "oprot#writeMessageEnd;" << endl <<

      indent() << "oprot#getTransport#flush" << endl;

    indent_down();

    indent_down();

    if (!(*f_iter)->is_oneway()) {

      std::string resultname = decapitalize((*f_iter)->get_name() + "_result");

      t_struct noargs(program_);

      t_function recv_function((*f_iter)->get_returntype(),

                               string("recv_") + (*f_iter)->get_name(),

                               &noargs);

      // Open function

      f_service_ <<

        indent() << "method private " << function_signature(&recv_function) << " =" << endl;

      indent_up();

      // TODO(mcslee): Validate message reply here, seq ids etc.

      f_service_ <<

        indent() << "let (fname, mtype, rseqid) = iprot#readMessageBegin in" << endl;

      indent_up();

      f_service_ <<

        indent() << "(if mtype = Protocol.EXCEPTION then" << endl <<

        indent() << "  let x = Application_Exn.read iprot in" << endl;

      indent_up();

      f_service_ <<

        indent() << "  (iprot#readMessageEnd;" <<

        indent() << "   raise (Application_Exn.E x))" << endl;

      indent_down();

      f_service_ <<

        indent() << "else ());" << endl;

      string res = "_";

      t_struct* xs = (*f_iter)->get_xceptions();

      const std::vector<t_field*>& xceptions = xs->get_members();

      if (!(*f_iter)->get_returntype()->is_void() || xceptions.size() > 0) {

        res = "result";

      }

      f_service_ <<

        indent() << "let "<<res<<" = read_" << resultname << " iprot in" << endl;

      indent_up();

      f_service_ <<

        indent() << "iprot#readMessageEnd;" << endl;

      // Careful, only return _result if not a void function

      if (!(*f_iter)->get_returntype()->is_void()) {

        f_service_ <<

          indent() << "match result#get_success with Some v -> v | None -> (" << endl;

        indent_up();

      }

      vector<t_field*>::const_iterator x_iter;

      for (x_iter = xceptions.begin(); x_iter != xceptions.end(); ++x_iter) {

        f_service_ <<

          indent() << "(match result#get_" << (*x_iter)->get_name() << " with None -> () | Some _v ->" << endl;

        indent(f_service_) << "  raise (" << capitalize(type_name((*x_iter)->get_type())) << " _v));" << endl;

      }

      // Careful, only return _result if not a void function

      if ((*f_iter)->get_returntype()->is_void()) {

        indent(f_service_) <<

          "()" << endl;

      } else {

        f_service_ <<

          indent() << "raise (Application_Exn.E (Application_Exn.create Application_Exn.MISSING_RESULT \"" << (*f_iter)->get_name() << " failed: unknown result\")))" << endl;

        indent_down();

      }

      // Close function

      indent_down();

      indent_down();

      indent_down();

    }

  }

  indent_down();

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

  indent(f_service_i_) << "end" << endl << endl;

}

/**

 * Generates a service server definition.

 *

 * @param tservice The service to generate a server for.

 */

void t_ocaml_generator::generate_service_server(t_service* tservice) {

  // Generate the dispatch methods

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

  vector<t_function*>::iterator f_iter;

  // Generate the header portion

  indent(f_service_) <<

    "class processor (handler : iface) =" << endl << indent() << "object (self)" << endl;

  indent(f_service_i_) <<

    "class processor : iface ->" << endl << indent() << "object" << endl;