Sacado_mpl_enable_if.hpp

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//                           Sacado Package
//                 Copyright (2006) Sandia Corporation
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#ifndef SACADO_MPL_ENABLE_IF_HPP
#define SACADO_MPL_ENABLE_IF_HPP

namespace Sacado {

  namespace mpl {

    template <bool, typename T = void>
    struct enable_if_c {};

    template <typename T>
    struct enable_if_c<true, T> {
      typedef T type;
    };

    template <class Cond, typename T = void>
    struct enable_if
      : enable_if_c<Cond::value, T> {};

    template <bool, typename T = void>
    struct lazy_enable_if_c {};

    template <typename T>
    struct lazy_enable_if_c<true, T> {
      typedef typename T::type type;
    };

    template <class Cond, typename T = void>
    struct lazy_enable_if
      : lazy_enable_if_c<Cond::value, T> {};

  }

}

#endif // SACADO_MPL_ENABLE_IF_HPP