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// Copyright (c) 2001-2010 Hartmut Kaiser
// Copyright (c) 2001-2010 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)
///////////////////////////////////////////////////////////////////////////////
//
// A complex number micro generator.
//
// [ HK July 7, 2009 ] spirit2
//
///////////////////////////////////////////////////////////////////////////////
#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/karma.hpp>
#include <boost/phoenix/core.hpp>
#include <boost/phoenix/operator.hpp>
#include <boost/fusion/include/std_pair.hpp>
#include <iostream>
#include <string>
#include <complex>
namespace client
{
///////////////////////////////////////////////////////////////////////////
// Our complex number parser/compiler (that's just a copy of the complex
// number example from Qi (see examples/qi/complex_number.cpp)
///////////////////////////////////////////////////////////////////////////
template <typename Iterator>
bool parse_complex(Iterator first, Iterator last, std::complex<double>& c)
{
using boost::spirit::qi::double_;
using boost::spirit::qi::_1;
using boost::spirit::qi::phrase_parse;
using boost::spirit::ascii::space;
using boost::phoenix::ref;
double rN = 0.0;
double iN = 0.0;
bool r = phrase_parse(first, last,
(
'(' >> double_[ref(rN) = _1]
>> -(',' >> double_[ref(iN) = _1]) >> ')'
| double_[ref(rN) = _1]
),
space);
if (!r || first != last) // fail if we did not get a full match
return false;
c = std::complex<double>(rN, iN);
return r;
}
///////////////////////////////////////////////////////////////////////////
// Our complex number generator
///////////////////////////////////////////////////////////////////////////
//[tutorial_karma_complex_number
template <typename OutputIterator>
bool generate_complex(OutputIterator sink, std::complex<double> const& c)
{
using boost::spirit::karma::eps;
using boost::spirit::karma::double_;
using boost::spirit::karma::_1;
using boost::spirit::karma::generate;
return generate(sink,
// Begin grammar
(
eps(c.imag() != 0) <<
'(' << double_[_1 = c.real()] << ", " << double_[_1 = c.imag()] << ')'
| double_[_1 = c.real()]
)
// End grammar
);
}
//]
}
///////////////////////////////////////////////////////////////////////////////
// Main program
///////////////////////////////////////////////////////////////////////////////
int main()
{
std::cout << "/////////////////////////////////////////////////////////\n\n";
std::cout << "\t\tA complex number micro generator for Spirit...\n\n";
std::cout << "/////////////////////////////////////////////////////////\n\n";
std::cout << "Give me a complex number of the form r or (r) or (r,i) \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;
std::complex<double> c;
if (client::parse_complex(str.begin(), str.end(), c))
{
std::cout << "-------------------------\n";
std::string generated;
std::back_insert_iterator<std::string> sink(generated);
if (!client::generate_complex(sink, c))
{
std::cout << "-------------------------\n";
std::cout << "Generating failed\n";
std::cout << "-------------------------\n";
}
else
{
std::cout << "-------------------------\n";
std::cout << "Generated: " << generated << "\n";
std::cout << "-------------------------\n";
}
}
else
{
std::cout << "-------------------------\n";
std::cout << "Parsing failed\n";
std::cout << "-------------------------\n";
}
}
std::cout << "Bye... :-) \n\n";
return 0;
}