Re: [Boost-users] [spirit] Qi rule for GPS NMEA

On 09/05/2013 07:00 PM, Michael Powell wrote:

On Thu, Sep 5, 2013 at 8:54 PM, Michael Caisse wrote:

...

Hi Michael -

Parsing NMEA is about as easy as you have described in english.

rule = lit('$') >> ~char_('*') >> lit('$') >> hex >> lit("\r\n");

Pretty straightforward. How about the wrinkle of enforcing the NMEA 2-hex-digit checksum?

It ends up that the Spirit numeric parser is customizable. Simply create the parser you want. For example: qi::uint_parser< unsigned, 16, 2, 2 > nmea_hex_p; creates a parser that will synthesize unsigned values that are parsed as base 16 and must have exactly 2 digits. rule >> lit('$') >> ~char_('*') >> '*' >> nmea_hex_p >> "\r\n"; michael -- Michael Caisse ciere consulting ciere.com