67 lines
1.6 KiB
C++
67 lines
1.6 KiB
C++
// Copyright (c) 2002
|
|
// Utrecht University (The Netherlands),
|
|
// ETH Zurich (Switzerland),
|
|
// INRIA Sophia-Antipolis (France),
|
|
// Max-Planck-Institute Saarbruecken (Germany),
|
|
// and Tel-Aviv University (Israel). All rights reserved.
|
|
//
|
|
// This file is part of CGAL (www.cgal.org)
|
|
//
|
|
// $URL: https://github.com/CGAL/cgal/blob/v5.1/Kernel_23/include/CGAL/Is_a_predicate.h $
|
|
// $Id: Is_a_predicate.h 0779373 2020-03-26T13:31:46+01:00 Sébastien Loriot
|
|
// SPDX-License-Identifier: LGPL-3.0-or-later OR LicenseRef-Commercial
|
|
//
|
|
//
|
|
// Author(s) : Sylvain Pion
|
|
|
|
#ifndef CGAL_IS_A_PREDICATE_H
|
|
#define CGAL_IS_A_PREDICATE_H
|
|
|
|
// How to determine if a kernel functor is a predicate or a construction.
|
|
|
|
#include <CGAL/basic.h>
|
|
#include <CGAL/enum.h>
|
|
|
|
namespace CGAL {
|
|
|
|
namespace internal {
|
|
|
|
// By default it's a construction
|
|
template <typename Return_type>
|
|
struct Return_type_of_predicate {
|
|
typedef CGAL::Tag_false type;
|
|
};
|
|
|
|
// Specializations for predicates
|
|
template <>
|
|
struct Return_type_of_predicate<bool> {
|
|
typedef CGAL::Tag_true type;
|
|
};
|
|
|
|
template <>
|
|
struct Return_type_of_predicate<CGAL::Sign> {
|
|
typedef CGAL::Tag_true type;
|
|
};
|
|
|
|
template <>
|
|
struct Return_type_of_predicate<CGAL::Bounded_side> {
|
|
typedef CGAL::Tag_true type;
|
|
};
|
|
|
|
template <>
|
|
struct Return_type_of_predicate<CGAL::Angle> {
|
|
typedef CGAL::Tag_true type;
|
|
};
|
|
|
|
} // namespace internal
|
|
|
|
template <typename Functor>
|
|
struct Is_a_predicate {
|
|
typedef typename internal::Return_type_of_predicate<
|
|
typename Functor::result_type>::type type;
|
|
};
|
|
|
|
} //namespace CGAL
|
|
|
|
#endif // CGAL_IS_A_PREDICATE_H
|