Function or functor calling using sprit boost parser library rule to save values in vector c++

Question

I want to parse this line and storing all hex values in functor <005F> <0061> [<00660066> <00660069> <00660066006C>] this values in txt file

Answer 1

Here's a sample doing this using Spirit V2

Live On Coliru

#define BOOST_SPIRIT_DEBUG
#include <boost/spirit/include/qi.hpp>
namespace qi  = boost::spirit::qi;

int main() {
    typedef std::string::const_iterator It;
    std::string const line = "<005F> <0061> [<00660066> <00660069> <00660066006C>]";

    It f = line.begin(), l = line.end();

    qi::int_parser<uintmax_t, 16> hex_int;
    qi::rule<It, uintmax_t()> braced_hex = '<' >> hex_int >> '>';
    BOOST_SPIRIT_DEBUG_NODE(braced_hex);

    std::vector<uintmax_t> list;
    bool result = qi::phrase_parse(f, l, *braced_hex >> '[' >> *braced_hex >> ']', qi::space, list);

    if (result) {
        std::cout << "Parse success: " << list.size() << "\n";

        for (auto& v : list)
            std::cout << v << " ";
    }
    else {
        std::cout << "Parse failed\n";
    }

    if (f!=l) {
        std::cout << "Remaining unparsed: '" << std::string(f,l) << "'\n";
    }
}

Output:

Parse success: 5
95 97 6684774 6684777 438093348972 

Debug output (if enabled):

<braced_hex>
    <try><005F> <0061> [<0066</try>
    <success> <0061> [<00660066> </success>
    <attributes>[95]</attributes>
</braced_hex>
<braced_hex>
    <try><0061> [<00660066> <</try>
    <success> [<00660066> <006600</success>
    <attributes>[97]</attributes>
</braced_hex>
<braced_hex>
    <try>[<00660066> <0066006</try>
    <fail/>
</braced_hex>
<braced_hex>
    <try><00660066> <00660069</try>
    <success> <00660069> <0066006</success>
    <attributes>[6684774]</attributes>
</braced_hex>
<braced_hex>
    <try><00660069> <00660066</try>
    <success> <00660066006C>]</success>
    <attributes>[6684777]</attributes>
</braced_hex>
<braced_hex>
    <try><00660066006C>]</try>
    <success>]</success>
    <attributes>[438093348972]</attributes>
</braced_hex>
<braced_hex>
    <try>]</try>
    <fail/>
</braced_hex>

Note that on my system int wasn't big enough to hold those numbers, so parse would fail. For maximum range I used intmax_t but you can use other types, including arbitrary precision types:

• 128 bit string to array using boost::spirit::*

Also note I prefer not to use semantic actions, using automatic attribute propagation. This is really prevalent in Spirit V2. See also

• Boost Spirit: "Semantic actions are evil"?