| // Copyright (c) 2010 Lars Kielhorn |
| // Copyright (c) 2001-2010 Hartmut Kaiser |
| // |
| // 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) |
| |
| #include <boost/config/warning_disable.hpp> |
| #include <boost/detail/lightweight_test.hpp> |
| #include <boost/spirit/include/karma.hpp> |
| |
| #include <iostream> |
| #include <string> |
| #include <iterator> |
| |
| namespace karma = boost::spirit::karma; |
| |
| // define a new real number formatting policy |
| template <typename Num> |
| struct scientific_policy : karma::real_policies<Num> |
| { |
| // we want the numbers always to be in scientific format |
| static int floatfield(Num n) { return std::ios_base::scientific; } |
| }; |
| |
| int main() |
| { |
| // define a new generator type based on the new policy |
| typedef karma::real_generator<double, scientific_policy<double> > |
| science_type; |
| science_type const scientific = science_type(); |
| |
| std::string output; |
| typedef std::back_insert_iterator<std::string> output_iterator; |
| output_iterator sink(output); |
| |
| // should output: 1.0e-01, but will output: 10.0e-02 |
| BOOST_TEST(karma::generate(sink, scientific, 0.1) && output == "1.0e-01"); |
| |
| return boost::report_errors(); |
| }; |