Re: x3 grammar rules

[...]
> Basically, I'd like to know if I'm going about the grammar correctly
> as I'm trying to parse the entire file at once.
> 
>      namespace client {
>          // ...
> 
>          // parse line of characters
>          x3::rule<class _desc> const _desc = "_desc";
>          auto const _desc_def = *(char_ - eol);
>          BOOST_SPIRIT_DEFINE(_desc);
> 
>          // parse 1 2 3
>          x3::rule<class _number> const _number = "_number";
>          auto const _number_def = int_ >> int_ >> int_;
>          BOOST_SPIRIT_DEFINE(_number);
> 
>          // parse 1 0.0 0.0 0.0
>          x3::rule<class _point> const _point = "_point";
>          auto const _point_def = int_ >> double_ >> double_ >> double_;
>          BOOST_SPIRIT_DEFINE(_point);
> 
>          // parse int chars int int int "1 tri 1 2 3"
>          x3::rule<class _element> const _element = "_element";
>          auto const _element_def = int_ >> *(char_) >> int_ >> int_ >> int_;
>          BOOST_SPIRIT_DEFINE(_element);
> 
>          // parse int int int "4 5 6"
>          x3::rule<class _elem_points> const _elem_points = "_elem_points";
>          auto const _elem_points_def = int_ >> int_ >> int_;
>          BOOST_SPIRIT_DEFINE(_elem_points);
> 
>          x3::rule<class _group> const _group = "_group";
>          auto const _group_def = int_ >> *(char_);
>          BOOST_SPIRIT_DEFINE(_group);
> 
>          auto description = skip(blank) [
>              *(_desc >> eol)
>          ];
> 
>          auto numbers = skip(blank) [
>              *(_number >> eol)
>          ];
> 
>          auto point = skip(blank) [
>              *(_point >> eol)
>          ];
> 
>          // parse two lines instead of 2nd line which looks the same, but
>          // has no element before it
>          // 1 tri  1 2 3
>          // 4 5 6
>          auto element = skip(blank) [
>              *(_element >> eol >> _elem_points >> eol)
>          ];
> 
>          auto group = skip(blank) [
>              *(_group >> eol)
>          ];
> 
>          auto pr = [&] (auto& ctx) {
>              std::cout << "hi " << std::endl;
>              //cout << "desc = " << _attr(ctx) << endl;
>          };
> 
>          auto const input = description[pr]
>              >> numbers[pr]
>              >> point[pr]
>              >> element[pr]
>              >> group[pr];
>          }
>      }
> 
>      int main() {
>          // ...
> 
>          mapped_file_source map(fil);
>          istringstream iss(map.data());
>          map.close();
> 
>          boost::spirit::istream_iterator iter(iss >> noskipws), eof;
> 
>          x3::parse(iter, eof,  client::input);
> 
>          return (iter != eof);
>      }
> 
> And the file I'm trying to parse is formatted as follows, only much larger.
> 
>      my file description
>      1 2 3
>      1 0.0 0.0 0.0
>      2 0.0 0.0 0.0
>      3 0.0 0.0 0.0
>      1 tri 1 3 1
>      1 2 3
>      2 tri 1 3 1
>      4 5 6
>      3 tri 1 3 1
>      7 8 9
>      1 end
> 
> Here is the output of running this. I get a 'hi' for each rule, but I
> don't get an error saying it didn't parse the entire file. Can anyone
> offer some guidance.

at the end of input file, is 'end' at the last line a keyword and your 
marker for EOL since I've not seen a rule for the keyword 'end'. This 
would explain the remainding iter != eof

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