spirit/example/x3/num_list/num_list1.cpp
2015-05-15 04:14:07 +08:00

88 lines
2.9 KiB
C++

/*=============================================================================
Copyright (c) 2002-2015 Joel de Guzman
Distributed under the Boost Software License, Version 1.0. (See accompanying
file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
=============================================================================*/
///////////////////////////////////////////////////////////////////////////////
//
// This sample demontrates a parser for a comma separated list of numbers.
// No semantic actions.
//
// [ JDG May 10, 2002 ] spirit1
// [ JDG March 24, 2007 ] spirit2
// [ JDG May 12, 2015 ] spirit X3
//
///////////////////////////////////////////////////////////////////////////////
#include <boost/config/warning_disable.hpp>
#include <boost/spirit/home/x3.hpp>
#include <iostream>
#include <string>
#include <vector>
namespace client
{
namespace x3 = boost::spirit::x3;
namespace ascii = boost::spirit::x3::ascii;
///////////////////////////////////////////////////////////////////////////
// Our number list parser
///////////////////////////////////////////////////////////////////////////
template <typename Iterator>
bool parse_numbers(Iterator first, Iterator last)
{
using x3::double_;
using x3::phrase_parse;
using ascii::space;
bool r = phrase_parse(
first, // Start Iterator
last, // End Iterator
double_ >> *(',' >> double_), // The Parser
space // The Skip-Parser
);
if (first != last) // fail if we did not get a full match
return false;
return r;
}
}
////////////////////////////////////////////////////////////////////////////
// Main program
////////////////////////////////////////////////////////////////////////////
int
main()
{
std::cout << "/////////////////////////////////////////////////////////\n\n";
std::cout << "\t\tA comma separated list parser for Spirit...\n\n";
std::cout << "/////////////////////////////////////////////////////////\n\n";
std::cout << "Give me a comma separated list of numbers.\n";
std::cout << "Type [q or Q] to quit\n\n";
std::string str;
while (getline(std::cin, str))
{
if (str.empty() || str[0] == 'q' || str[0] == 'Q')
break;
if (client::parse_numbers(str.begin(), str.end()))
{
std::cout << "-------------------------\n";
std::cout << "Parsing succeeded\n";
std::cout << str << " Parses OK: " << std::endl;
}
else
{
std::cout << "-------------------------\n";
std::cout << "Parsing failed\n";
std::cout << "-------------------------\n";
}
}
std::cout << "Bye... :-) \n\n";
return 0;
}