xref: /trunk/main/autodoc/inc/cosv/tpl/processor.hxx (revision 11c03c6d)
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21 
22 
23 
24 #ifndef CSV_TPL_PROCESSOR_HXX
25 #define CSV_TPL_PROCESSOR_HXX
26 
27 // USED SERVICES
28 
29 
30 
31 
32 namespace csv
33 {
34 
35 
36 /** Implements an acyclic visitor pattern. This is the abstract
37     base for the classes doing the work (the "visitors").
38 */
39 class ProcessorIfc
40 {
41   public:
~ProcessorIfc()42     virtual             ~ProcessorIfc() {}
43 };
44 
45 
46 
47 /** Implements an acyclic visitor pattern. This is the abstract
48     base for the classes to be processed (the "visitables").
49 */
50 class ConstProcessorClient
51 {
52   public:
~ConstProcessorClient()53     virtual             ~ConstProcessorClient() {}
54 
Accept(ProcessorIfc & io_processor) const55     void                Accept(
56                             ProcessorIfc &  io_processor ) const
57                             { do_Accept(io_processor); }
58   private:
59     virtual void        do_Accept(
60                             ProcessorIfc &  io_processor ) const = 0;
61 };
62 
63 /** Implements an acyclic visitor pattern. This is the abstract
64     base for the classes to be processed (the "visitables").
65 */
66 class ProcessorClient
67 {
68   public:
~ProcessorClient()69     virtual             ~ProcessorClient() {}
70 
Accept(ProcessorIfc & io_processor)71     void                Accept(
72                             ProcessorIfc &  io_processor )
73                             { do_Accept(io_processor); }
74   private:
75     virtual void        do_Accept(
76                             ProcessorIfc &  io_processor ) = 0;
77 };
78 
79 
80 
81 
82 
83 /** Typed base for "visitor" classes, leaving the visited
84     object const.
85 
86     @see ProcessorIfc
87     @see Processor<>
88 */
89 template <typename X, typename R = void>
90 class ConstProcessor
91 {
92   public:
~ConstProcessor()93     virtual             ~ConstProcessor() {}
94 
Process(const X & i_object)95     R                   Process(
96                             const X &           i_object )
97                         { return do_Process(i_object ); }
98  private:
99     virtual R           do_Process(
100                             const X &           i_object ) = 0;
101 };
102 
103 
104 /** Typed base for "visitor" classes which may change the visited
105     object.
106 
107     @see ProcessorIfc
108     @see ConstProcessor<>
109 */
110 template <typename X, typename R = void>
111 class Processor
112 {
113   public:
~Processor()114     virtual             ~Processor() {}
115 
Process(X & i_object)116     R                   Process(
117                             X &                 i_object )
118                         { return do_Process(i_object ); }
119  private:
120     virtual R           do_Process(
121                             X &                 i_object ) = 0;
122 };
123 
124 
125 template <class C>
126 inline void
CheckedCall(ProcessorIfc & io_processor,const C & i_client)127 CheckedCall( ProcessorIfc &  io_processor,
128              const C &       i_client )
129 {
130     ConstProcessor<C> *
131         pProcessor = dynamic_cast< csv::ConstProcessor<C> * >
132                         (&io_processor);
133     if (pProcessor != 0)
134         pProcessor->Process(i_client);
135 }
136 
137 template <class C>
138 inline void
CheckedCall(ProcessorIfc & io_processor,C & io_client)139 CheckedCall( ProcessorIfc &  io_processor,
140              C &             io_client )
141 {
142     Processor<C> *
143         pProcessor = dynamic_cast< csv::Processor<C> * >
144                         (&io_processor);
145     if (pProcessor != 0)
146         pProcessor->Process(io_client);
147 }
148 
149 template <class C>
150 inline void
AssertedCall(ProcessorIfc & io_processor,const C & i_client)151 AssertedCall( ProcessorIfc &  io_processor,
152               const C &       i_client )
153 {
154     ConstProcessor<C> *
155         pProcessor = dynamic_cast< csv::ConstProcessor<C> * >
156                         (&io_processor);
157     csv_assert( pProcessor != 0
158                 && "csv::AssertedCall() failed. Processed object did not match processor." );
159     pProcessor->Process(i_client);
160 }
161 
162 template <class C>
163 inline void
AssertedCall(ProcessorIfc & io_processor,C & io_client)164 AssertedCall( ProcessorIfc &  io_processor,
165               C &             io_client )
166 {
167     Processor<C> *
168         pProcessor = dynamic_cast< csv::Processor<C> * >
169                         (&io_processor);
170     csv_assert( pProcessor != 0
171                 && "csv::AssertedCall() failed. Processed object did not match processor." );
172     pProcessor->Process(io_client);
173 }
174 
175 
176 
177 
178 }   // namespace csv
179 #endif
180