mapnik/include/mapnik/boolean.hpp

99 lines
2.5 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2011 Artem Pavlenko
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*****************************************************************************/
#ifndef MAPNIK_BOOLEAN_HPP
#define MAPNIK_BOOLEAN_HPP
// std
#include <istream>
#include <algorithm>
#include <string>
#include <iostream>
namespace mapnik
{
// Helper for class bool
class boolean {
public:
boolean()
: b_(false) {}
boolean(bool b)
: b_(b) {}
boolean(boolean const& b)
: b_(b.b_) {}
operator bool() const
{
return b_;
}
boolean & operator =(boolean const& other)
{
if (this == &other)
return *this;
b_ = other.b_;
return *this;
}
private:
bool b_;
};
// Special stream input operator for boolean values
template <typename charT, typename traits>
std::basic_istream<charT, traits> &
operator >> ( std::basic_istream<charT, traits> & s, boolean & b )
{
std::string word;
s >> word;
std::transform(word.begin(), word.end(), word.begin(), ::tolower);
if ( s )
{
if ( word == "true" || word == "yes" || word == "on" ||
word == "1")
{
b = true;
}
else if ( word == "false" || word == "no" || word == "off" ||
word == "0")
{
b = false;
}
else
{
s.setstate( std::ios::failbit );
}
}
return s;
}
template <typename charT, typename traits>
std::basic_ostream<charT, traits> &
operator << ( std::basic_ostream<charT, traits> & s, boolean const& b )
{
s << ( b ? "true" : "false" );
return s;
}
}
#endif // MAPNIK_BOOLEAN_HPP