11.6.   421

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11.6.  

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  ( 11.24).

//  11.24.   language_processor
//                   process_input

class language_processor {

//. . .
protected:

virtual bool getString(void) = 0;

virtual bool validateString(void) = 0;

virtual bool parseString(void) = 0;

II...
public:

bool process_input(void) ;

};

bool language_processor::process_input(void)
{