is_implicit_cast_allowed.h

/*  This file is part of the Vc library. {{{
Copyright © 2015 Matthias Kretz <kretz@kde.org>
 
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      documentation and/or other materials provided with the distribution.
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      names of its contributors may be used to endorse or promote products
      derived from this software without specific prior written permission.
 
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}}}*/
 
#ifndef VC_TRAITS_IS_IMPLICIT_CAST_ALLOWED_H_
#define VC_TRAITS_IS_IMPLICIT_CAST_ALLOWED_H_
 
namespace Vc_VERSIONED_NAMESPACE
{
namespace Traits
{
template <typename From, typename To, bool = std::is_integral<From>::value>
struct is_implicit_cast_allowed
    : public std::integral_constant<
          bool, std::is_same<From, To>::value ||
                    (std::is_integral<To>::value &&
                     (std::is_same<typename std::make_unsigned<From>::type, To>::value ||
                      std::is_same<typename std::make_signed<From>::type, To>::value))> {
};
 
template <typename From, typename To>
struct is_implicit_cast_allowed<From, To, false> : public std::is_same<From, To>::type {
};
 
template <typename From, typename To>
struct is_implicit_cast_allowed_mask : public is_implicit_cast_allowed<From, To> {
};
}  // namespace Traits
}  // namespace Vc
 
#endif  // VC_TRAITS_IS_IMPLICIT_CAST_ALLOWED_H_
 
// vim: foldmethod=marker