value.hh
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00001 #ifndef TYPELIB_VALUE_HH
00002 #define TYPELIB_VALUE_HH
00003 
00004 #include "typemodel.hh"
00005 #include "typevisitor.hh"
00006 #include "registry.hh"
00007 #include <boost/ref.hpp>
00008 
00009 namespace Typelib
00010 {
00020     class Value
00021     {
00022         void*       m_data;
00023         boost::reference_wrapper<Type const> m_type;
00024         
00025     public:
00026         Value()
00027             : m_data(0), m_type(Registry::null()) {}
00028 
00029         Value(void* data, Type const& type)
00030             : m_data(data), m_type(type) {}
00031 
00033         void* getData() const { return m_data; }
00035         Type const& getType() const { return m_type; }
00036 
00037         bool operator == (Value const& with) const
00038         { return (m_data == with.m_data) && (m_type.get() == with.m_type.get()); }
00039         bool operator != (Value const& with) const
00040         { return (m_data != with.m_data) || (m_type.get() != with.m_type.get()); }
00041     };
00042 
00045     class ValueVisitor
00046     {
00047         class TypeDispatch;
00048         friend class TypeDispatch;
00049         bool m_defval;
00050 
00051         TypeDispatch* m_dispatcher;
00052 
00053     protected:
00054         virtual bool visit_ (int8_t  &) { return m_defval; }
00055         virtual bool visit_ (uint8_t &) { return m_defval; }
00056         virtual bool visit_ (int16_t &) { return m_defval; }
00057         virtual bool visit_ (uint16_t&) { return m_defval; }
00058         virtual bool visit_ (int32_t &) { return m_defval; }
00059         virtual bool visit_ (uint32_t&) { return m_defval; }
00060         virtual bool visit_ (int64_t &) { return m_defval; }
00061         virtual bool visit_ (uint64_t&) { return m_defval; }
00062         virtual bool visit_ (float   &) { return m_defval; }
00063         virtual bool visit_ (double  &) { return m_defval; }
00064 
00065         virtual bool visit_ (Value const& v, OpaqueType const& t);
00066         virtual bool visit_ (Value const& v, Pointer const& t);
00067         virtual bool visit_ (Value const& v, Array const& a);
00068         virtual bool visit_ (Value const& v, Container const& a);
00069         virtual bool visit_ (Value const& v, Compound const& c); 
00070         virtual bool visit_ (Value const& v, Compound const& c, Field const& f);
00071         virtual bool visit_ (Enum::integral_type& v, Enum const& e);
00072 
00073     public:
00074         ValueVisitor(bool defval = false);
00075         virtual ~ValueVisitor();
00076 
00078         virtual void dispatch(Value v);
00079 
00080         void apply(Value v);
00081     };
00082 
00085     class BadValueCast : public std::exception {};
00086 
00088     class FieldNotFound : public BadValueCast 
00089     {
00090     public:
00091         ~FieldNotFound() throw() {}
00092         std::string const name;
00093         FieldNotFound(std::string const& name_)
00094             : name(name_) {}
00095     };
00096 
00099     class FieldGetter : public ValueVisitor
00100     {
00101         std::string m_name;
00102         Value m_field;
00103 
00104         using ValueVisitor::visit_;
00105 
00106         bool visit_(Compound const& type) { return true; }
00107         bool visit_(Value const& value, Compound const&, Field const& field)
00108         {
00109             if (field.getName() == m_name)
00110             {
00111                 m_field = value;
00112                 return false;
00113             }
00114             return true;
00115         }
00116         
00117     public:
00118         FieldGetter()
00119             : ValueVisitor(true) {}
00120         Value apply(Value v, std::string const& name)
00121         {
00122             m_name = name;
00123             m_field = Value();
00124             ValueVisitor::apply(v);
00125             if (! m_field.getData())
00126                 throw FieldNotFound(name);
00127             return m_field;
00128         }
00129         
00130     };
00131 
00134     inline Value value_get_field(Value v, std::string const& name)
00135     {
00136         FieldGetter getter;
00137         return getter.apply(v, name);
00138     }
00139 
00142     inline Value value_get_field(void* ptr, Type const& type, std::string const& name)
00143     {
00144         Value v(ptr, type);
00145         return value_get_field(v, name);
00146     }
00147 }
00148 
00149 #endif
00150 


typelib
Author(s): Sylvain Joyeux/sylvain.joyeux@m4x.org
autogenerated on Sat Jun 8 2019 18:49:22