Struct template opt_parser

Boost C++ Libraries

Struct template opt_parser

boost::parser::opt_parser

Synopsis

// In header: <boost/parser/parser.hpp>

template<typename Parser> 
struct opt_parser {

  // public member functions
  template<typename Iter, typename Sentinel, typename Context, 
           typename SkipParser> 
     (, , , , 
              , ) ;
  template<typename Iter, typename Sentinel, typename Context, 
           typename SkipParser, typename Attribute> 
     (, , , , 
              , , ) ;

  // public data members
   parser_;
};

Description

Repeats the application of another parser of type Parser, [0, 1] times. The parse always succeeds. The attribute produced is a std::optional<T>, where T is the type of attribute produced by Parser.

`opt_parser` public member functions

template<typename Iter, typename Sentinel, typename Context, 
         typename SkipParser> 
   ( first,  last,  context, 
             skip,  flags,  success) ;

template<typename Iter, typename Sentinel, typename Context, 
         typename SkipParser, typename Attribute> 
   ( first,  last,  context, 
             skip,  flags,  success, 
             retval) ;