cpp_introspection: cpp_introspection: conversion.h Source File

00001 //=================================================================================================
00002 // Copyright (c) 2011, Johannes Meyer, TU Darmstadt
00003 // All rights reserved.
00004 
00005 // Redistribution and use in source and binary forms, with or without
00006 // modification, are permitted provided that the following conditions are met:
00007 //     * Redistributions of source code must retain the above copyright
00008 //       notice, this list of conditions and the following disclaimer.
00009 //     * Redistributions in binary form must reproduce the above copyright
00010 //       notice, this list of conditions and the following disclaimer in the
00011 //       documentation and/or other materials provided with the distribution.
00012 //     * Neither the name of the Flight Systems and Automatic Control group,
00013 //       TU Darmstadt, nor the names of its contributors may be used to
00014 //       endorse or promote products derived from this software without
00015 //       specific prior written permission.
00016 
00017 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
00018 // ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
00019 // WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
00020 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE FOR ANY
00021 // DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
00022 // (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
00023 // LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
00024 // ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
00025 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
00026 // SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00027 //=================================================================================================
00028 
00029 #ifndef CPP_INTROSPECTION_CONVERSION_H
00030 #define CPP_INTROSPECTION_CONVERSION_H
00031 
00032 #include <boost/type_traits.hpp>
00033 #include <boost/utility/enable_if.hpp>
00034 #include <introspection/type.h>
00035 
00036 namespace cpp_introspection {
00037 
00038   template <
00039     typename OtherT,
00040     typename Enabled = void
00041   >
00042   struct converter {
00043     static OtherT to(const Type& type, const boost::any& value)   { return OtherT(); }
00044     static boost::any from(const Type& type, const OtherT& value) { return boost::any(); }
00045   };
00046 
00047   // floating_point
00048   template <typename OtherT>
00049   struct converter<OtherT, typename boost::enable_if<boost::is_floating_point<OtherT> >::type>
00050   {
00051     static OtherT to(const Type& type, const boost::any& value)   { return OtherT(type.as_double(value)); }
00052     static boost::any from(const Type& type, const OtherT& value) { return type.from_double(value); }
00053   };
00054 
00055   // signed
00056   template <typename OtherT>
00057   struct converter<OtherT, typename boost::enable_if<boost::is_signed<OtherT> >::type> {
00058     static OtherT to(const Type& type, const boost::any& value)   { return OtherT(type.as_int(value)); }
00059     static boost::any from(const Type& type, const OtherT& value) { return type.from_int(value); }
00060   };
00061 
00062   // unsigned
00063   template <typename OtherT>
00064   struct converter<OtherT, typename boost::enable_if<boost::is_unsigned<OtherT> >::type> {
00065     static OtherT to(const Type& type, const boost::any& value)   { return OtherT(type.as_unsigned(value)); }
00066     static boost::any from(const Type& type, const OtherT& value) { return type.from_unsigned(value); }
00067   };
00068 
00069   // string
00070   template <>
00071   struct converter<std::string> {
00072     static std::string to(const Type& type, const boost::any& value)   { return type.as_string(value); }
00073     static boost::any from(const Type& type, const std::string& value) { return type.from_string(value); }
00074   };
00075 
00076   template <typename TargetType> TargetType Type::as(const boost::any& value) const   { return converter<TargetType>::to(*this, value); }
00077   template <typename SourceType> boost::any Type::from(const SourceType& value) const { return converter<SourceType>::from(*this, value); }
00078 
00079 } // namespace cpp_introspection
00080 
00081 #endif // CPP_INTROSPECTION_CONVERSION_H