The Spirit Parser Library: Inline Parsing in C++

Listing 6: The class declaration of abstract_parser and concrete_parser

//  Copyright (c) 2001, Joel de Guzman and Dan Nuffer
//  Permission is granted to use this code without restriction as
//  long as this copyright notice appears in all source files.

template <typename IteratorT>
class abstract_parser
{
public:
                    abstract_parser() {}
    virtual         ~abstract_parser() {}
    virtual match   parse(
                        IteratorT& first,
                        IteratorT const& last) const = 0;
};

template <typename ParserT, typename IteratorT>
class concrete_parser
    : public ParserT
    , public abstract_parser<IteratorT>
{
public:

                    concrete_parser(ParserT const& parser)
                    : ParserT(parser) {}
  virtual           ~concrete_parser() {}

  virtual match
  parse(IteratorT& first, IteratorT const& last) const
  { return ParserT::parse(first, last); }
};