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alliecat · Guest

Hi Group,

I'm starting to learn to use boost::spirit but I am having a problem
understanding the behaviour of a simple example. Any suggestions and
corrections would be appreciated.

Just as a test, I'd like to parse this string:
"SET albert fred 123"
with the "SET" being identified as a keyword, and the "123" identified
as an integer, and "albert" and "fred" identified as names.

To my surprise, the output from the code below is:
SET
NAME='albert fred 123'

rather than (what *I* thought I'd get)
SET
NAME='albert'
NAME='fred'
INT=123

Any suggestions?

Thanks,
Stuart Allie

Sample code:
------------
#include <iostream>
#include <string>
#include <boost/spirit/core.hpp>
#include <boost/spirit/utility.hpp>

using namespace boost::spirit;

void do_set(const char* first, const char* last) {
std::cout << "SETn";
};

void do_int(int val) {
std::cout << "INT=" << val << "n";
};

void do_name(const char* first, const char* last) {
std::string s(first, last);
std::cout << "NAME='" << s << "'n";
};

int main (int argc, char** argv) {
parse( "SET albert fred 123",

*( str_p("SET")[&do_set]

Carl Barron · Guest

In article <1106183680.357405.165990 (AT) c13g2000cwb (DOT) googlegroups.com>,
alliecat <stuart.allie (AT) hydro (DOT) com.au> wrote:

Thomas Guest · Guest

Stuart,

You should use boost::spirit::lexeme_d to turn off whitespace skipping
for your "name" parser.

lexeme_d[alpha_p >> *alnum_p][&do_name]

By the way, you don't need the semi-colons at the end of functions.
Regards, Thomas

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