Teuchos_as.hpp

// @HEADER
// ***********************************************************************
//
//                    Teuchos: Common Tools Package
//                 Copyright (2004) Sandia Corporation
//
// Under terms of Contract DE-AC04-94AL85000, there is a non-exclusive
// license for use of this work by or on behalf of the U.S. Government.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// 1. Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// 3. Neither the name of the Corporation nor the names of the
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY SANDIA CORPORATION "AS IS" AND ANY
// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SANDIA CORPORATION OR THE
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Questions? Contact Michael A. Heroux (maherou@sandia.gov)
//
// ***********************************************************************
// @HEADER

#ifndef TEUCHOS_AS_HPP
#define TEUCHOS_AS_HPP

#include "Teuchos_Assert.hpp"

#ifdef HAVE_TEUCHOS_QD
#include <qd/qd_real.h>
#include <qd/dd_real.h>
#endif

namespace Teuchos {


template<class TypeTo, class TypeFrom>
class ValueTypeConversionTraits {
public:
  static TypeTo convert( const TypeFrom t )
    {
      return t;
      // This default implementation is just an implicit conversion and will
      // generate compiler warning on dangerous conversions.
    }
  static TypeTo safeConvert( const TypeFrom t )
    {
      return t;
      // This default implementation is just an implicit conversion and will
      // generate compiler warning on dangerous conversions.  No runtime
      // checking can be done by default; only specializations can define
      // meaningful and portable runtime checks of conversions.
    }
};

template<class TypeTo, class TypeFrom>
inline TypeTo as( const TypeFrom& t )
{
#ifdef TEUCHOS_DEBUG
  return ValueTypeConversionTraits<TypeTo,TypeFrom>::safeConvert(t);
#else
  return ValueTypeConversionTraits<TypeTo,TypeFrom>::convert(t);
#endif
}


template<class TypeTo, class TypeFrom>
inline TypeTo asSafe( const TypeFrom& t )
{
  return ValueTypeConversionTraits<TypeTo,TypeFrom>::safeConvert(t);
}


template <class TypeTo> 
class asFunc {
  public:
  asFunc() {}

  template <class TypeFrom>
  inline TypeTo operator()(const TypeFrom &t) {
    return as<TypeTo>(t);
  }
};


//
// Standard specializations of ValueTypeConversionTraits
//


template<int N>
class ValueTypeConversionTraits<std::string, char[N]> {
public:
  static std::string convert( const char t[] )
    { return std::string(t); }
  static std::string safeConvert( const char t[] )
    { return std::string(t); }
};

#ifdef HAVE_TEUCHOS_QD

template <>
class ValueTypeConversionTraits<double, qd_real> {
public:
  inline static double convert( const qd_real t )
    { return to_double(t); }
  inline static double safeConvert( const qd_real t )
    { return to_double(t); }
};

template <>
class ValueTypeConversionTraits<float, qd_real> {
public:
  inline static float convert( const qd_real t )
    { return (float)to_double(t); }
  inline static float safeConvert( const qd_real t )
    { return (float)to_double(t); }
};

template <>
class ValueTypeConversionTraits<int, qd_real> {
public:
  inline static int convert( const qd_real t )
    { return to_int(t); }
  inline static int safeConvert( const qd_real t )
    { return to_int(t); }
};

template <>
class ValueTypeConversionTraits<dd_real, qd_real> {
public:
  inline static dd_real convert( const qd_real t )
    { return to_dd_real(t); }
  inline static dd_real safeConvert( const qd_real t )
    { return to_dd_real(t); }
};

template <>
class ValueTypeConversionTraits<double, dd_real> {
public:
  inline static double convert( const dd_real t )
    { return to_double(t); }
  inline static double safeConvert( const dd_real t )
    { return to_double(t); }
};

template <>
class ValueTypeConversionTraits<float, dd_real> {
public:
  inline static float convert( const dd_real t )
    { return (float)to_double(t); }
  inline static float safeConvert( const dd_real t )
    { return (float)to_double(t); }
};

template <>
class ValueTypeConversionTraits<int, dd_real> {
public:
  inline static int convert( const dd_real t )
    { return to_int(t); }
  inline static int safeConvert( const dd_real t )
    { return to_int(t); }
};

#endif

// ToDo: Add more specializations as needed!


} // end namespace Teuchos


#endif // TEUCHOS_AS_HPP