source: lemon-0.x/src/lemon/bits/item_writer.h @ 1429:4283998fb2be

/* -*- C++ -*-
 * src/lemon/bits/item_reader.h - Part of LEMON, a generic C++ optimization library
 *
 * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
 * (Egervary Research Group on Combinatorial Optimization, EGRES).
 *
 * Permission to use, modify and distribute this software is granted
 * provided that this copyright notice appears in all copies. For
 * precise terms see the accompanying LICENSE file.
 *
 * This software is provided "AS IS" with no warranty of any kind,
 * express or implied, and with no claim as to its suitability for any
 * purpose.
 *
 */

/// \ingroup item_io
/// \file
/// \brief Item writer bits for lemon output.

#ifndef LEMON_BITS_ITEM_WRITER_H
#define LEMON_BITS_ITEM_WRITER_H

#include <iostream>
#include <string>

#include <vector>
#include <deque>
#include <list>
#include <set>

namespace lemon {
  
  template <typename Value>
  class DefaultWriter;

  /// \ingroup item_io
  /// \brief Writer class for quoted strings.
  ///
  /// Writer class for quoted strings. It can process the escape
  /// sequences in the string.
  /// \author Balazs Dezso
  class QuotedStringWriter {
  public:
    typedef std::string Value;

    /// \brief Constructor for the writer.
    ///
    /// Constructor for the writer. If the given parameter is true
    /// the writer creates escape sequences from special characters.
    QuotedStringWriter(bool _escaped = true) : escaped(_escaped) {}

    /// \brief Writes a quoted string to the given stream.
    ///
    /// Writes a quoted string to the given stream.
    void write(std::ostream& os, const std::string& value) {
      os << "\"";
      if (escaped) {
        std::ostringstream ls;
        for (int i = 0; i < (int)value.size(); ++i) {
          writeEscape(ls, value[i]);
        }
        os << ls.str();
      } else {
        os << value;
      }
      os << "\"";
    }

  private:
    
    static void writeEscape(std::ostream& os, char c) {
      switch (c) {
      case '\\':
        os << "\\\\";
        return;
      case '\"':
        os << "\\\"";
        return;
      case '\'':
        os << "\\\'";
        return;
      case '\?':
        os << "\\\?";
        return;
      case '\a':
        os << "\\a";
        return;
      case '\b':
        os << "\\b";
        return;
      case '\f':
        os << "\\f";
        return;
      case '\r':
        os << "\\r";
        return;
      case '\n':
        os << "\\n";
        return;
      case '\t':
        os << "\\t";
        return;
      case '\v':
        os << "\\v";
        return;
      default:
        if (c < 0x20) {
          os << '\\' << std::oct << (int)c;
        } else {
          os << c;
        }
        return;
      }     
    }
  private:
    bool escaped;
  };

  /// \ingroup item_io
  ///
  /// \brief Writer for standard containers.
  ///
  /// Writer for each iterable standard containers. The representation
  /// of the container is the values enumerated between an open and a
  /// close parse. 
  ///
  /// \author Balazs Dezso
  template <
    typename _Container, 
    typename _ItemWriter = DefaultWriter<typename _Container::value_type> 
  >
  class IterableWriter {
  public:
    typedef _Container Value;
    typedef _ItemWriter ItemWriter;

  private:

    ItemWriter item_writer;

  public:

    /// \brief Writes the values of the container to the given stream.
    ///
    /// Writes the values of the container to the given stream.
    void write(std::ostream& os, const Value& value) const {
      typename Value::const_iterator it;
      os << '(';
      for (it = value.begin(); it != value.end(); ++it) {
        item_writer.write(os, *it);
        os << ' ';
      }
      os << ')';
    }

  };

  /// \ingroup item_io
  /// 
  /// \brief The default item writer template class.
  ///
  /// The default item writer template class. If some section writer
  /// needs to write a value to the stream it will give the default way for it.
  ///
  /// \author Balazs Dezso
  template <typename _Value>
  class DefaultWriter {
  public:
    /// The value type.
    typedef _Value Value;
    /// \brief Writes the value to the given stream.
    ///
    /// Writes the value to the given stream.
    void write(std::ostream& os, const Value& value) const {
      os << value;
    }
  };

  template <>
  class DefaultWriter<std::string> 
    : public QuotedStringWriter<std::string> {};

  template <typename Item>
  class DefaultWriter<std::vector<Item> > 
    : public IterableWriter<std::vector<Item> > {};

  template <typename Item>
  class DefaultWriter<std::deque<Item> > 
    : public IterableWriter<std::deque<Item> > {};

  template <typename Item>
  class DefaultWriter<std::list<Item> > 
    : public IterableWriter<std::list<Item> > {};
  
  template <typename Item>
  class DefaultWriter<std::set<Item> > 
    : public IterableWriter<std::set<Item> > {};

  template <typename Item>
  class DefaultWriter<std::multiset<Item> > 
    : public IterableWriter<std::multiset<Item> > {};

  /// \ingroup item_io
  /// \brief Standard WriterTraits for the section writers.
  ///
  /// Standard WriterTraits for the section writers.
  /// It defines standard writing method for all type of value. 
  /// \author Balazs Dezso
  struct DefaultWriterTraits {

    template <typename _Value>
    struct Writer : DefaultWriter<_Value> {};

  };

}

#endif