epoc32/include/stdapis/boost/dynamic_property_map.hpp
author William Roberts <williamr@symbian.org>
Wed, 31 Mar 2010 12:27:01 +0100
branchSymbian2
changeset 3 e1b950c65cb4
permissions -rw-r--r--
Attempt to represent the S^2->S^3 header reorganisation as a series of "hg rename" operations
     1 #ifndef DYNAMIC_PROPERTY_MAP_RG09302004_HPP
     2 #define DYNAMIC_PROPERTY_MAP_RG09302004_HPP
     3 
     4 // Copyright 2004-5 The Trustees of Indiana University.
     5 
     6 // Use, modification and distribution is subject to the Boost Software
     7 // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
     8 // http://www.boost.org/LICENSE_1_0.txt)
     9 
    10 //  dynamic_property_map.hpp -
    11 //    Support for runtime-polymorphic property maps.  This header is factored
    12 //  out of Doug Gregor's routines for reading GraphML files for use in reading
    13 //  GraphViz graph files.
    14 
    15 //  Authors: Doug Gregor
    16 //           Ronald Garcia
    17 //
    18 
    19 
    20 #include <boost/config.hpp>
    21 #include <boost/property_map.hpp>
    22 #include <boost/lexical_cast.hpp>
    23 #include <boost/any.hpp>
    24 #include <boost/function/function3.hpp>
    25 #include <boost/type_traits/is_convertible.hpp>
    26 #include <typeinfo>
    27 #include <boost/mpl/bool.hpp>
    28 #include <stdexcept>
    29 #include <sstream>
    30 #include <map>
    31 #include <boost/type.hpp>
    32 
    33 namespace boost {
    34 
    35 namespace detail {
    36 
    37   // read_value -
    38   //   A wrapper around lexical_cast, which does not behave as
    39   //   desired for std::string types.
    40   template<typename Value>
    41   inline Value read_value(const std::string& value)
    42   { return boost::lexical_cast<Value>(value); }
    43 
    44   template<>
    45   inline std::string read_value<std::string>(const std::string& value)
    46   { return value; }
    47 
    48 }
    49 
    50 
    51 // dynamic_property_map -
    52 //  This interface supports polymorphic manipulation of property maps.
    53 class dynamic_property_map
    54 {
    55 public:
    56   virtual ~dynamic_property_map() { }
    57 
    58   virtual boost::any get(const any& key) = 0;
    59   virtual std::string get_string(const any& key) = 0;
    60   virtual void put(const any& key, const any& value) = 0;
    61   virtual const std::type_info& key() const = 0;
    62   virtual const std::type_info& value() const = 0;
    63 };
    64 
    65 
    66 //////////////////////////////////////////////////////////////////////
    67 // Property map exceptions
    68 //////////////////////////////////////////////////////////////////////
    69 
    70 struct dynamic_property_exception : public std::exception {
    71   virtual ~dynamic_property_exception() throw() {}
    72   virtual const char* what() const throw() = 0;
    73 };
    74 
    75 struct property_not_found : public dynamic_property_exception {
    76   std::string property;
    77   mutable std::string statement;
    78   property_not_found(const std::string& property) : property(property) {}
    79   virtual ~property_not_found() throw() {}
    80 
    81   const char* what() const throw() {
    82     if(statement.empty())
    83       statement =
    84         std::string("Property not found: ") + property + ".";
    85 
    86     return statement.c_str();
    87   }
    88 };
    89 
    90 struct dynamic_get_failure : public dynamic_property_exception {
    91   std::string property;
    92   mutable std::string statement;
    93   dynamic_get_failure(const std::string& property) : property(property) {}
    94   virtual ~dynamic_get_failure() throw() {}
    95 
    96   const char* what() const throw() {
    97     if(statement.empty())
    98       statement =
    99         std::string(
   100          "dynamic property get cannot retrieve value for  property: ")
   101         + property + ".";
   102 
   103     return statement.c_str();
   104   }
   105 };
   106 
   107 struct dynamic_const_put_error  : public dynamic_property_exception {
   108   virtual ~dynamic_const_put_error() throw() {}
   109 
   110   const char* what() const throw() {
   111     return "Attempt to put a value into a const property map: ";
   112   }
   113 };
   114 
   115 
   116 namespace detail {
   117 
   118 //
   119 // dynamic_property_map_adaptor -
   120 //   property-map adaptor to support runtime polymorphism.
   121 template<typename PropertyMap>
   122 class dynamic_property_map_adaptor : public dynamic_property_map
   123 {
   124   typedef typename property_traits<PropertyMap>::key_type key_type;
   125   typedef typename property_traits<PropertyMap>::value_type value_type;
   126   typedef typename property_traits<PropertyMap>::category category;
   127 
   128   // do_put - overloaded dispatches from the put() member function.
   129   //   Attempts to "put" to a property map that does not model
   130   //   WritablePropertyMap result in a runtime exception.
   131 
   132   //   in_value must either hold an object of value_type or a string that
   133   //   can be converted to value_type via iostreams.
   134   void do_put(const any& in_key, const any& in_value, mpl::bool_<true>)
   135   {
   136 #if !(defined(__GNUC__) && (__GNUC__ == 2) && (__GNUC_MINOR__ == 95))
   137     using boost::put;
   138 #endif
   139 
   140     key_type key = any_cast<key_type>(in_key);
   141     if (in_value.type() == typeid(value_type)) {
   142 #if defined(__GNUC__) && (__GNUC__ == 2) && (__GNUC_MINOR__ == 95)
   143       boost::put(property_map, key, any_cast<value_type>(in_value));
   144 #else
   145       put(property_map, key, any_cast<value_type>(in_value));
   146 #endif
   147     } else {
   148       //  if in_value is an empty string, put a default constructed value_type.
   149       std::string v = any_cast<std::string>(in_value);
   150       if (v.empty()) {
   151 #if defined(__GNUC__) && (__GNUC__ == 2) && (__GNUC_MINOR__ == 95)
   152         boost::put(property_map, key, value_type());
   153 #else
   154         put(property_map, key, value_type());
   155 #endif
   156       } else {
   157 #if defined(__GNUC__) && (__GNUC__ == 2) && (__GNUC_MINOR__ == 95)
   158         boost::put(property_map, key, detail::read_value<value_type>(v));
   159 #else
   160         put(property_map, key, detail::read_value<value_type>(v));
   161 #endif
   162       }
   163     }
   164   }
   165 
   166   void do_put(const any&, const any&, mpl::bool_<false>)
   167   {
   168     throw dynamic_const_put_error();
   169   }
   170 
   171 public:
   172   explicit dynamic_property_map_adaptor(const PropertyMap& property_map)
   173     : property_map(property_map) { }
   174 
   175   virtual boost::any get(const any& key)
   176   {
   177 #if defined(__GNUC__) && (__GNUC__ == 2) && (__GNUC_MINOR__ == 95)
   178     return boost::get(property_map, any_cast<key_type>(key));
   179 #else
   180     using boost::get;
   181 
   182     return get(property_map, any_cast<key_type>(key));
   183 #endif
   184   }
   185 
   186   virtual std::string get_string(const any& key)
   187   {
   188 #if defined(__GNUC__) && (__GNUC__ == 2) && (__GNUC_MINOR__ == 95)
   189     std::ostringstream out;
   190     out << boost::get(property_map, any_cast<key_type>(key));
   191     return out.str();
   192 #else
   193     using boost::get;
   194 
   195     std::ostringstream out;
   196     out << get(property_map, any_cast<key_type>(key));
   197     return out.str();
   198 #endif
   199   }
   200 
   201   virtual void put(const any& in_key, const any& in_value)
   202   {
   203     do_put(in_key, in_value,
   204            mpl::bool_<(is_convertible<category*,
   205                                       writable_property_map_tag*>::value)>());
   206   }
   207 
   208   virtual const std::type_info& key()   const { return typeid(key_type); }
   209   virtual const std::type_info& value() const { return typeid(value_type); }
   210 
   211   PropertyMap&       base()       { return property_map; }
   212   const PropertyMap& base() const { return property_map; }
   213 
   214 private:
   215   PropertyMap property_map;
   216 };
   217 
   218 } // namespace detail
   219 
   220 //
   221 // dynamic_properties -
   222 //   container for dynamic property maps
   223 //
   224 struct dynamic_properties
   225 {
   226   typedef std::multimap<std::string, dynamic_property_map*>
   227     property_maps_type;
   228   typedef boost::function3<std::auto_ptr<dynamic_property_map>,
   229                            const std::string&,
   230                            const boost::any&,
   231                            const boost::any&> generate_fn_type;
   232 public:
   233 
   234   typedef property_maps_type::iterator iterator;
   235   typedef property_maps_type::const_iterator const_iterator;
   236 
   237   dynamic_properties() : generate_fn() { }
   238   dynamic_properties(const generate_fn_type& g) : generate_fn(g) {}
   239 
   240   ~dynamic_properties()
   241   {
   242     for (property_maps_type::iterator i = property_maps.begin();
   243          i != property_maps.end(); ++i) {
   244       delete i->second;
   245     }
   246   }
   247 
   248   template<typename PropertyMap>
   249   dynamic_properties&
   250   property(const std::string& name, PropertyMap property_map)
   251   {
   252     // Tbd: exception safety
   253     std::auto_ptr<dynamic_property_map> pm(
   254       new detail::dynamic_property_map_adaptor<PropertyMap>(property_map));
   255     property_maps_type::iterator i =
   256       property_maps.insert(property_maps_type::value_type(name, 0));
   257     i->second = pm.release();
   258 
   259     return *this;
   260   }
   261 
   262   iterator       begin()       { return property_maps.begin(); }
   263   const_iterator begin() const { return property_maps.begin(); }
   264   iterator       end()         { return property_maps.end(); }
   265   const_iterator end() const   { return property_maps.end(); }
   266 
   267   iterator lower_bound(const std::string& name)
   268   { return property_maps.lower_bound(name); }
   269 
   270   const_iterator lower_bound(const std::string& name) const
   271   { return property_maps.lower_bound(name); }
   272 
   273   void
   274   insert(const std::string& name, std::auto_ptr<dynamic_property_map> pm)
   275   {
   276     property_maps.insert(property_maps_type::value_type(name, pm.release()));
   277   }
   278 
   279   template<typename Key, typename Value>
   280   std::auto_ptr<dynamic_property_map>
   281   generate(const std::string& name, const Key& key, const Value& value)
   282   {
   283     if(!generate_fn) {
   284       throw property_not_found(name);
   285     } else {
   286       return generate_fn(name,key,value);
   287     }
   288   }
   289 
   290 private:
   291   property_maps_type property_maps;
   292   generate_fn_type generate_fn;
   293 };
   294 
   295 template<typename Key, typename Value>
   296 bool
   297 put(const std::string& name, dynamic_properties& dp, const Key& key,
   298     const Value& value)
   299 {
   300   for (dynamic_properties::iterator i = dp.lower_bound(name);
   301        i != dp.end() && i->first == name; ++i) {
   302     if (i->second->key() == typeid(key)) {
   303       i->second->put(key, value);
   304       return true;
   305     }
   306   }
   307 
   308   std::auto_ptr<dynamic_property_map> new_map = dp.generate(name, key, value);
   309   if (new_map.get()) {
   310     new_map->put(key, value);
   311     dp.insert(name, new_map);
   312     return true;
   313   } else {
   314     return false;
   315   }
   316 }
   317 
   318 #ifndef BOOST_NO_EXPLICIT_FUNCTION_TEMPLATE_ARGUMENTS 
   319 template<typename Value, typename Key>
   320 Value
   321 get(const std::string& name, const dynamic_properties& dp, const Key& key)
   322 {
   323   for (dynamic_properties::const_iterator i = dp.lower_bound(name);
   324        i != dp.end() && i->first == name; ++i) {
   325     if (i->second->key() == typeid(key))
   326       return any_cast<Value>(i->second->get(key));
   327   }
   328 
   329   throw dynamic_get_failure(name);
   330 }
   331 #endif
   332 
   333 template<typename Value, typename Key>
   334 Value
   335 get(const std::string& name, const dynamic_properties& dp, const Key& key, type<Value>)
   336 {
   337   for (dynamic_properties::const_iterator i = dp.lower_bound(name);
   338        i != dp.end() && i->first == name; ++i) {
   339     if (i->second->key() == typeid(key))
   340       return any_cast<Value>(i->second->get(key));
   341   }
   342 
   343   throw dynamic_get_failure(name);
   344 }
   345 
   346 template<typename Key>
   347 std::string
   348 get(const std::string& name, const dynamic_properties& dp, const Key& key)
   349 {
   350   for (dynamic_properties::const_iterator i = dp.lower_bound(name);
   351        i != dp.end() && i->first == name; ++i) {
   352     if (i->second->key() == typeid(key))
   353       return i->second->get_string(key);
   354   }
   355 
   356   throw dynamic_get_failure(name);
   357 }
   358 
   359 
   360 }
   361 
   362 #endif // DYNAMIC_PROPERTY_MAP_RG09302004_HPP