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SigmaeInitialization.cc

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    DataTree.cc 18.96 KiB
    /*
     * Copyright (C) 2003-2018 Dynare Team
     *
     * This file is part of Dynare.
     *
     * Dynare is free software: you can redistribute it and/or modify
     * it under the terms of the GNU General Public License as published by
     * the Free Software Foundation, either version 3 of the License, or
     * (at your option) any later version.
     *
     * Dynare is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     * GNU General Public License for more details.
     *
     * You should have received a copy of the GNU General Public License
     * along with Dynare.  If not, see <http://www.gnu.org/licenses/>.
     */
    
    #include <cstdlib>
    #include <cassert>
    #include <iostream>
    #include <regex>
    
    #include <boost/filesystem.hpp>
    
    #include "DataTree.hh"
    
    DataTree::DataTree(SymbolTable &symbol_table_arg,
                       NumericalConstants &num_constants_arg,
                       ExternalFunctionsTable &external_functions_table_arg) :
      symbol_table(symbol_table_arg),
      num_constants(num_constants_arg),
      external_functions_table(external_functions_table_arg)
    {
      Zero = AddNonNegativeConstant("0");
      One = AddNonNegativeConstant("1");
      Two = AddNonNegativeConstant("2");
    
      MinusOne = AddUMinus(One);
    
      NaN = AddNonNegativeConstant("NaN");
      Infinity = AddNonNegativeConstant("Inf");
      MinusInfinity = AddUMinus(Infinity);
    
      Pi = AddNonNegativeConstant("3.141592653589793");
    }
    
    DataTree::~DataTree() = default;
    
    expr_t
    DataTree::AddNonNegativeConstant(const string &value)
    {
      int id = num_constants.AddNonNegativeConstant(value);
    
      auto it = num_const_node_map.find(id);
      if (it != num_const_node_map.end())
        return it->second;
    
      auto sp = make_unique<NumConstNode>(*this, node_list.size(), id);
      auto p = sp.get();
      node_list.push_back(move(sp));
      num_const_node_map[id] = p;
      return p;
    }
    
    VariableNode *
    DataTree::AddVariableInternal(int symb_id, int lag)
    {
      auto it = variable_node_map.find({ symb_id, lag });
      if (it != variable_node_map.end())
        return it->second;
    
      auto sp = make_unique<VariableNode>(*this, node_list.size(), symb_id, lag);
      auto p = sp.get();
      node_list.push_back(move(sp));
      variable_node_map[{ symb_id, lag }] = p;
      return p;
    }
    
    bool
    DataTree::ParamUsedWithLeadLagInternal() const
    {
      for (const auto & it : variable_node_map)
        if (symbol_table.getType(it.first.first) == SymbolType::parameter && it.first.second != 0)
          return true;
      return false;
    }
    
    VariableNode *
    DataTree::AddVariable(int symb_id, int lag)
    {
      assert(lag == 0);
      return AddVariableInternal(symb_id, lag);
    }
    
    expr_t
    DataTree::AddPlus(expr_t iArg1, expr_t iArg2)
    {
      if (iArg1 != Zero && iArg2 != Zero)
        {
          // Simplify x+(-y) in x-y
          auto *uarg2 = dynamic_cast<UnaryOpNode *>(iArg2);
          if (uarg2 != nullptr && uarg2->get_op_code() == UnaryOpcode::uminus)
            return AddMinus(iArg1, uarg2->get_arg());
    
          // To treat commutativity of "+"
          // Nodes iArg1 and iArg2 are sorted by index
          if (iArg1->idx > iArg2->idx)
            {
              expr_t tmp = iArg1;
              iArg1 = iArg2;
              iArg2 = tmp;
            }
          return AddBinaryOp(iArg1, BinaryOpcode::plus, iArg2);
        }
      else if (iArg1 != Zero)
        return iArg1;
      else if (iArg2 != Zero)
        return iArg2;
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddMinus(expr_t iArg1, expr_t iArg2)
    {
      if (iArg2 == Zero)
        return iArg1;
    
      if (iArg1 == Zero)
        return AddUMinus(iArg2);
    
      if (iArg1 == iArg2)
        return Zero;
    
      return AddBinaryOp(iArg1, BinaryOpcode::minus, iArg2);
    }
    
    expr_t
    DataTree::AddUMinus(expr_t iArg1)
    {
      if (iArg1 != Zero)
        {
          // Simplify -(-x) in x
          auto *uarg = dynamic_cast<UnaryOpNode *>(iArg1);
          if (uarg != nullptr && uarg->get_op_code() == UnaryOpcode::uminus)
            return uarg->get_arg();
    
          return AddUnaryOp(UnaryOpcode::uminus, iArg1);
        }
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddTimes(expr_t iArg1, expr_t iArg2)
    {
      if (iArg1 == MinusOne)
        return AddUMinus(iArg2);
      else if (iArg2 == MinusOne)
        return AddUMinus(iArg1);
      else if (iArg1 != Zero && iArg1 != One && iArg2 != Zero && iArg2 != One)
        {
          // To treat commutativity of "*"
          // Nodes iArg1 and iArg2 are sorted by index
          if (iArg1->idx > iArg2->idx)
            {
              expr_t tmp = iArg1;
              iArg1 = iArg2;
              iArg2 = tmp;
            }
          return AddBinaryOp(iArg1, BinaryOpcode::times, iArg2);
        }
      else if (iArg1 != Zero && iArg1 != One && iArg2 == One)
        return iArg1;
      else if (iArg2 != Zero && iArg2 != One && iArg1 == One)
        return iArg2;
      else if (iArg2 == One && iArg1 == One)
        return One;
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddDivide(expr_t iArg1, expr_t iArg2) noexcept(false)
    {
      if (iArg2 == One)
        return iArg1;
    
      // This test should be before the next two, otherwise 0/0 won't be rejected
      if (iArg2 == Zero)
        {
          cerr << "ERROR: Division by zero!" << endl;
          throw DivisionByZeroException();
        }
    
      if (iArg1 == Zero)
        return Zero;
    
      if (iArg1 == iArg2)
        return One;
    
      return AddBinaryOp(iArg1, BinaryOpcode::divide, iArg2);
    }
    
    expr_t
    DataTree::AddLess(expr_t iArg1, expr_t iArg2)
    {
      return AddBinaryOp(iArg1, BinaryOpcode::less, iArg2);
    }
    
    expr_t
    DataTree::AddGreater(expr_t iArg1, expr_t iArg2)
    {
      return AddBinaryOp(iArg1, BinaryOpcode::greater, iArg2);
    }
    
    expr_t
    DataTree::AddLessEqual(expr_t iArg1, expr_t iArg2)
    {
      return AddBinaryOp(iArg1, BinaryOpcode::lessEqual, iArg2);
    }
    
    expr_t
    DataTree::AddGreaterEqual(expr_t iArg1, expr_t iArg2)
    {
      return AddBinaryOp(iArg1, BinaryOpcode::greaterEqual, iArg2);
    }
    
    expr_t
    DataTree::AddEqualEqual(expr_t iArg1, expr_t iArg2)
    {
      return AddBinaryOp(iArg1, BinaryOpcode::equalEqual, iArg2);
    }
    
    expr_t
    DataTree::AddDifferent(expr_t iArg1, expr_t iArg2)
    {
      return AddBinaryOp(iArg1, BinaryOpcode::different, iArg2);
    }
    
    expr_t
    DataTree::AddPower(expr_t iArg1, expr_t iArg2)
    {
      if (iArg1 != Zero && iArg2 != Zero && iArg1 != One && iArg2 != One)
        return AddBinaryOp(iArg1, BinaryOpcode::power, iArg2);
      else if (iArg1 == One)
        return One;
      else if (iArg2 == One)
        return iArg1;
      else if (iArg2 == Zero)
        return One;
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddPowerDeriv(expr_t iArg1, expr_t iArg2, int powerDerivOrder)
    {
      assert(powerDerivOrder > 0);
      return AddBinaryOp(iArg1, BinaryOpcode::powerDeriv, iArg2, powerDerivOrder);
    }
    
    expr_t
    DataTree::AddDiff(expr_t iArg1)
    {
      return AddUnaryOp(UnaryOpcode::diff, iArg1);
    }
    
    expr_t
    DataTree::AddAdl(expr_t iArg1, const string &name, const vector<int> &lags)
    {
      return AddUnaryOp(UnaryOpcode::adl, iArg1, 0, 0, 0, string(name), lags);
    }
    
    expr_t
    DataTree::AddExp(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::exp, iArg1);
      else
        return One;
    }
    
    expr_t
    DataTree::AddLog(expr_t iArg1)
    {
      if (iArg1 != Zero && iArg1 != One)
        return AddUnaryOp(UnaryOpcode::log, iArg1);
      else if (iArg1 == One)
        return Zero;
      else
        {
          cerr << "ERROR: log(0) not defined!" << endl;
          exit(EXIT_FAILURE);
        }
    }
    
    expr_t
    DataTree::AddLog10(expr_t iArg1)
    {
      if (iArg1 != Zero && iArg1 != One)
        return AddUnaryOp(UnaryOpcode::log10, iArg1);
      else if (iArg1 == One)
        return Zero;
      else
        {
          cerr << "ERROR: log10(0) not defined!" << endl;
          exit(EXIT_FAILURE);
        }
    }
    
    expr_t
    DataTree::AddCos(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::cos, iArg1);
      else
        return One;
    }
    
    expr_t
    DataTree::AddSin(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::sin, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddTan(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::tan, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddAcos(expr_t iArg1)
    {
      if (iArg1 != One)
        return AddUnaryOp(UnaryOpcode::acos, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddAsin(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::asin, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddAtan(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::atan, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddCosh(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::cosh, iArg1);
      else
        return One;
    }
    
    expr_t
    DataTree::AddSinh(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::sinh, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddTanh(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::tanh, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddAcosh(expr_t iArg1)
    {
      if (iArg1 != One)
        return AddUnaryOp(UnaryOpcode::acosh, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddAsinh(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::asinh, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddAtanh(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::atanh, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddSqrt(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::sqrt, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddAbs(expr_t iArg1)
    {
      if (iArg1 == Zero)
        return Zero;
      if (iArg1 == One)
        return One;
      else
        return AddUnaryOp(UnaryOpcode::abs, iArg1);
    }
    
    expr_t
    DataTree::AddSign(expr_t iArg1)
    {
      if (iArg1 == Zero)
        return Zero;
      if (iArg1 == One)
        return One;
      else
        return AddUnaryOp(UnaryOpcode::sign, iArg1);
    }
    
    expr_t
    DataTree::AddErf(expr_t iArg1)
    {
      if (iArg1 != Zero)
        return AddUnaryOp(UnaryOpcode::erf, iArg1);
      else
        return Zero;
    }
    
    expr_t
    DataTree::AddMax(expr_t iArg1, expr_t iArg2)
    {
      return AddBinaryOp(iArg1, BinaryOpcode::max, iArg2);
    }
    
    expr_t
    DataTree::AddMin(expr_t iArg1, expr_t iArg2)
    {
      return AddBinaryOp(iArg1, BinaryOpcode::min, iArg2);
    }
    
    expr_t
    DataTree::AddNormcdf(expr_t iArg1, expr_t iArg2, expr_t iArg3)
    {
      return AddTrinaryOp(iArg1, TrinaryOpcode::normcdf, iArg2, iArg3);
    }
    
    expr_t
    DataTree::AddNormpdf(expr_t iArg1, expr_t iArg2, expr_t iArg3)
    {
      return AddTrinaryOp(iArg1, TrinaryOpcode::normpdf, iArg2, iArg3);
    }
    
    expr_t
    DataTree::AddSteadyState(expr_t iArg1)
    {
      return AddUnaryOp(UnaryOpcode::steadyState, iArg1);
    }
    
    expr_t
    DataTree::AddSteadyStateParamDeriv(expr_t iArg1, int param_symb_id)
    {
      return AddUnaryOp(UnaryOpcode::steadyStateParamDeriv, iArg1, 0, param_symb_id);
    }
    
    expr_t
    DataTree::AddSteadyStateParam2ndDeriv(expr_t iArg1, int param1_symb_id, int param2_symb_id)
    {
      return AddUnaryOp(UnaryOpcode::steadyStateParam2ndDeriv, iArg1, 0, param1_symb_id, param2_symb_id);
    }
    
    expr_t
    DataTree::AddExpectation(int iArg1, expr_t iArg2)
    {
      return AddUnaryOp(UnaryOpcode::expectation, iArg2, iArg1);
    }
    
    expr_t
    DataTree::AddVarExpectation(const string &model_name)
    {
      auto it = var_expectation_node_map.find(model_name);
      if (it != var_expectation_node_map.end())
        return it->second;
    
      auto sp = make_unique<VarExpectationNode>(*this, node_list.size(), model_name);
      auto p = sp.get();
      node_list.push_back(move(sp));
      var_expectation_node_map[model_name] = p;
      return p;
    }
    
    expr_t
    DataTree::AddPacExpectation(const string &model_name)
    {
      auto it = pac_expectation_node_map.find(model_name);
      if (it != pac_expectation_node_map.end())
        return it->second;
    
      auto sp = make_unique<PacExpectationNode>(*this, node_list.size(), model_name);
      auto p = sp.get();
      node_list.push_back(move(sp));
      pac_expectation_node_map[model_name] = p;
      return p;
    }
    
    expr_t
    DataTree::AddEqual(expr_t iArg1, expr_t iArg2)
    {
      return AddBinaryOp(iArg1, BinaryOpcode::equal, iArg2);
    }
    
    void
    DataTree::AddLocalVariable(int symb_id, expr_t value) noexcept(false)
    {
      assert(symbol_table.getType(symb_id) == SymbolType::modelLocalVariable);
    
      // Throw an exception if symbol already declared
      auto it = local_variables_table.find(symb_id);
      if (it != local_variables_table.end())
        throw LocalVariableException(symbol_table.getName(symb_id));
    
      local_variables_table[symb_id] = value;
      local_variables_vector.push_back(symb_id);
    }
    
    expr_t
    DataTree::AddExternalFunction(int symb_id, const vector<expr_t> &arguments)
    {
      assert(symbol_table.getType(symb_id) == SymbolType::externalFunction);
    
      auto it = external_function_node_map.find({ arguments, symb_id });
      if (it != external_function_node_map.end())
        return it->second;
    
      auto sp = make_unique<ExternalFunctionNode>(*this, node_list.size(), symb_id, arguments);
      auto p = sp.get();
      node_list.push_back(move(sp));
      external_function_node_map[{ arguments, symb_id }] = p;
      return p;
    }
    
    expr_t
    DataTree::AddFirstDerivExternalFunction(int top_level_symb_id, const vector<expr_t> &arguments, int input_index)
    {
      assert(symbol_table.getType(top_level_symb_id) == SymbolType::externalFunction);
    
      auto it
        = first_deriv_external_function_node_map.find({ arguments, input_index, top_level_symb_id });
      if (it != first_deriv_external_function_node_map.end())
        return it->second;
    
      auto sp = make_unique<FirstDerivExternalFunctionNode>(*this, node_list.size(), top_level_symb_id, arguments, input_index);
      auto p = sp.get();
      node_list.push_back(move(sp));
      first_deriv_external_function_node_map[{ arguments, input_index, top_level_symb_id }] = p;
      return p;
    }
    
    expr_t
    DataTree::AddSecondDerivExternalFunction(int top_level_symb_id, const vector<expr_t> &arguments, int input_index1, int input_index2)
    {
      assert(symbol_table.getType(top_level_symb_id) == SymbolType::externalFunction);
    
      auto it
        = second_deriv_external_function_node_map.find({ arguments, input_index1, input_index2,
              top_level_symb_id });
      if (it != second_deriv_external_function_node_map.end())
        return it->second;
    
      auto sp = make_unique<SecondDerivExternalFunctionNode>(*this, node_list.size(), top_level_symb_id, arguments, input_index1, input_index2);
      auto p = sp.get();
      node_list.push_back(move(sp));
      second_deriv_external_function_node_map[{ arguments, input_index1, input_index2, top_level_symb_id }] = p;
      return p;
    }
    
    bool
    DataTree::isSymbolUsed(int symb_id) const
    {
      for (const auto & it : variable_node_map)
        if (it.first.first == symb_id)
          return true;
    
      if (local_variables_table.find(symb_id) != local_variables_table.end())
        return true;
    
      return false;
    }
    
    int
    DataTree::getDerivID(int symb_id, int lag) const noexcept(false)
    {
      throw UnknownDerivIDException();
    }
    
    SymbolType
    DataTree::getTypeByDerivID(int deriv_id) const noexcept(false)
    {
      throw UnknownDerivIDException();
    }
    
    int
    DataTree::getLagByDerivID(int deriv_id) const noexcept(false)
    {
      throw UnknownDerivIDException();
    }
    
    int
    DataTree::getSymbIDByDerivID(int deriv_id) const noexcept(false)
    {
      throw UnknownDerivIDException();
    }
    
    void
    DataTree::addAllParamDerivId(set<int> &deriv_id_set)
    {
    }
    
    int
    DataTree::getDynJacobianCol(int deriv_id) const noexcept(false)
    {
      throw UnknownDerivIDException();
    }
    
    bool
    DataTree::isUnaryOpUsed(UnaryOpcode opcode) const
    {
      for (const auto & it : unary_op_node_map)
        if (get<1>(it.first) == opcode)
          return true;
    
      return false;
    }
    
    bool
    DataTree::isBinaryOpUsed(BinaryOpcode opcode) const
    {
      for (const auto & it : binary_op_node_map)
        if (get<2>(it.first) == opcode)
          return true;
    
      return false;
    }
    
    bool
    DataTree::isTrinaryOpUsed(TrinaryOpcode opcode) const
    {
      for (const auto & it : trinary_op_node_map)
        if (get<3>(it.first) == opcode)
          return true;
    
      return false;
    }
    
    bool
    DataTree::isExternalFunctionUsed(int symb_id) const
    {
      for (const auto & it : external_function_node_map)
        if (it.first.second == symb_id)
          return true;
    
      return false;
    }
    
    bool
    DataTree::isFirstDerivExternalFunctionUsed(int symb_id) const
    {
      for (const auto & it : first_deriv_external_function_node_map)
        if (get<2>(it.first) == symb_id)
          return true;
    
      return false;
    }
    
    bool
    DataTree::isSecondDerivExternalFunctionUsed(int symb_id) const
    {
      for (const auto & it : second_deriv_external_function_node_map)
        if (get<3>(it.first) == symb_id)
          return true;
    
      return false;
    }
    
    int
    DataTree::minLagForSymbol(int symb_id) const
    {
      int r = 0;
      for (const auto & it : variable_node_map)
        if (it.first.first == symb_id && it.first.second < r)
          r = it.first.second;
      return r;
    }
    
    void
    DataTree::writePowerDerivCHeader(ostream &output) const
    {
      if (isBinaryOpUsed(BinaryOpcode::powerDeriv))
        output << "double getPowerDeriv(double, double, int);" << endl;
    }
    
    void
    DataTree::writePowerDeriv(ostream &output) const
    {
      if (isBinaryOpUsed(BinaryOpcode::powerDeriv))
        output << "/*" << endl
               << " * The k-th derivative of x^p" << endl
               << " */" << endl
               << "double getPowerDeriv(double x, double p, int k)" << endl
               << "{" << endl
               << "#ifdef _MSC_VER" << endl
               << "# define nearbyint(x) (fabs((x)-floor(x)) < fabs((x)-ceil(x)) ? floor(x) : ceil(x))" << endl
               << "#endif" << endl
               << "  if ( fabs(x) < " << near_zero << " && p > 0 && k > p && fabs(p-nearbyint(p)) < " << near_zero << " )" << endl
               << "    return 0.0;" << endl
               << "  else" << endl
               << "    {" << endl
               << "      int i = 0;" << endl
               << "      double dxp = pow(x, p-k);" << endl
               << "      for (; i<k; i++)" << endl
               << "        dxp *= p--;" << endl
               << "      return dxp;" << endl
               << "    }" << endl
               << "}" << endl;
    }
    
    void
    DataTree::writeNormcdfCHeader(ostream &output) const
    {
    #if defined(_WIN32) || defined(__CYGWIN32__) || defined(__MINGW32__)
      if (isTrinaryOpUsed(TrinaryOpcode::normcdf))
        output << "#ifdef _MSC_VER" << endl
               << "double normcdf(double);" << endl
               << "#endif" << endl;
    #endif
    }
    
    void
    DataTree::writeNormcdf(ostream &output) const
    {
    #if defined(_WIN32) || defined(__CYGWIN32__) || defined(__MINGW32__)
      if (isTrinaryOpUsed(TrinaryOpcode::normcdf))
        output << endl
               << "#ifdef _MSC_VER" << endl
               << "/*" << endl
               << " * Define normcdf for MSVC compiler" << endl
               << " */" << endl
               << "double normcdf(double x)" << endl
               << "{" << endl
               << "#if _MSC_VER >= 1700" << endl
               << "  return 0.5 * erfc(-x * M_SQRT1_2);" << endl
               << "#else" << endl
               << "  // From http://www.johndcook.com/blog/cpp_phi" << endl
               << "  double a1 =  0.254829592;" << endl
               << "  double a2 = -0.284496736;" << endl
               << "  double a3 =  1.421413741;" << endl
               << "  double a4 = -1.453152027;" << endl
               << "  double a5 =  1.061405429;" << endl
               << "  double p  =  0.3275911;" << endl
               << "  int sign = (x < 0) ? -1 : 1;" << endl
               << "  x = fabs(x)/sqrt(2.0);" << endl
               << "  // From the Handbook of Mathematical Functions by Abramowitz and Stegun, formula 7.1.26" << endl
               << "  double t = 1.0/(1.0 + p*x);" << endl
               << "  double y = 1.0 - (((((a5*t + a4)*t) + a3)*t + a2)*t + a1)*t*exp(-x*x);" << endl
               << "  return 0.5*(1.0 + sign*y);" << endl
               << "#endif" << endl
               << "}" << endl
               << "#endif" << endl;
    #endif
    }
    
    string
    DataTree::packageDir(const string &package)
    {
      regex pat{"\\."};
      string dirname = "+" + regex_replace(package, pat, "/+");
      boost::filesystem::create_directories(dirname);
      return dirname;
    }