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Struct template or_parser

boost::parser::or_parser

Synopsis

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

template<typename ParserTuple> 
struct or_parser {

  // public member functions
  or_parser(ParserTuple);
  template<typename Iter, typename Sentinel, typename Context, 
           typename SkipParser> 
    auto call(Iter &, Sentinel, Context const &, SkipParser const &, 
              unspecified, bool &) const;
  template<typename Iter, typename Sentinel, typename Context, 
           typename SkipParser, typename Attribute> 
    void call(Iter &, Sentinel, Context const &, SkipParser const &, 
              unspecified, bool &, Attribute &) const;

  // public data members
  ParserTuple parsers_;
};

Description

Applies each parser in ParserTuple, in order, stopping after the application of the first one that succeeds. The parse succeeds iff one of the sub-parsers succeeds. The attribute produced is a std::variant over the types of attribute produced by the parsers in ParserTuple.

`or_parser` public member functions

```
or_parser(ParserTuple parsers);
```

template<typename Iter, typename Sentinel, typename Context, 
         typename SkipParser> 
  auto call(Iter & first, Sentinel last, Context const & context, 
            SkipParser const & skip, unspecified flags, bool & success) const;

template<typename Iter, typename Sentinel, typename Context, 
         typename SkipParser, typename Attribute> 
  void call(Iter & first, Sentinel last, Context const & context, 
            SkipParser const & skip, unspecified flags, bool & success, 
            Attribute & retval) const;