Domain name parser not working

Hello,

// Where Let is char_(/*upper/lower-case chars*/), Dig is
char_("0123456789"), Hyp is char_('.'), and dot_ is '.'.

template<typename It>
struct DomainNameParser : boost::spirit::qi::grammar<It, Ast::Address()> {

  DomainNameParser() {

    _hyp = char_('-');
    _dig = char_(DOMAIN_NAME_PARSER_DIGITS);
    _let = char_(DOMAIN_NAME_PARSER_LOWERCASE DOMAIN_NAME_PARSER_UPPERCASE);

    // A straight interpretation of the Domain Name grammar leads me to this:
    /*qi::rule<It, std::string()>*/ _label = raw[_let >> -(*(_let |
_dig | _hyp) >> (_let | _dig))];
    /*qi::rule<It, Ast::Address()>*/ _start = (_label % dot_) >> eoi;
    // ...

 }
};

Assuming,

struct Address {
  std::vector<std::string> _labels;
};

BOOST_FUSION_ADAPT_STRUCT(Ast::Address,
    (std::vector<std::string>, _labels)
)

However, this is failing to match: "E-PHUMZ8G8j1KEZG26C" in spite of
the fact this matches the expected pattern. No skippers involved, just
the iterator (std::string::const_iterator), and the AST, of course.

For now, dropping the semantic action until I can get the parser to
work properly. However, eventually I want to incorporate the
validation rule:

struct label_validation {
    // Notwithstanding Qi/Fusion bits that glue it together.
    bool operator()(std::string const& l) const {
        return l.length() <= 63;
    }
};

Once again I am suspicious whether Optional is working properly, never
minding Kleene Star productions. I ended up needing to separate out
Alternative phrases instead of the Optional before in order to make it
work properly.

Perhaps I need to capture each phrase in a rule of its own focused
solely on std::string or char, respectively, as contrasted with the
entire std::string?

Cheers,

Michael Powell

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