dust3d/thirdparty/QuadriFlow/3rd/lemon-1.3.1/lemon/bits/enable_if.h

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/* -*- mode: C++; indent-tabs-mode: nil; -*-
*
* This file is a part of LEMON, a generic C++ optimization library.
*
* Copyright (C) 2003-2009
* Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
* (Egervary Research Group on Combinatorial Optimization, EGRES).
*
* Permission to use, modify and distribute this software is granted
* provided that this copyright notice appears in all copies. For
* precise terms see the accompanying LICENSE file.
*
* This software is provided "AS IS" with no warranty of any kind,
* express or implied, and with no claim as to its suitability for any
* purpose.
*
*/
// This file contains a modified version of the enable_if library from BOOST.
// See the appropriate copyright notice below.
// Boost enable_if library
// Copyright 2003 (c) The Trustees of Indiana University.
// Use, modification, and distribution is subject to the Boost Software
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt)
// Authors: Jaakko Jarvi (jajarvi at osl.iu.edu)
// Jeremiah Willcock (jewillco at osl.iu.edu)
// Andrew Lumsdaine (lums at osl.iu.edu)
#ifndef LEMON_BITS_ENABLE_IF_H
#define LEMON_BITS_ENABLE_IF_H
//\file
//\brief Miscellaneous basic utilities
namespace lemon
{
// Basic type for defining "tags". A "YES" condition for \c enable_if.
// Basic type for defining "tags". A "YES" condition for \c enable_if.
//
//\sa False
struct True {
//\e
static const bool value = true;
};
// Basic type for defining "tags". A "NO" condition for \c enable_if.
// Basic type for defining "tags". A "NO" condition for \c enable_if.
//
//\sa True
struct False {
//\e
static const bool value = false;
};
template <typename T>
struct Wrap {
const T &value;
Wrap(const T &t) : value(t) {}
};
/**************** dummy class to avoid ambiguity ****************/
template<int T> struct dummy { dummy(int) {} };
/**************** enable_if from BOOST ****************/
template <typename Type, typename T = void>
struct exists {
typedef T type;
};
template <bool B, class T = void>
struct enable_if_c {
typedef T type;
};
template <class T>
struct enable_if_c<false, T> {};
template <class Cond, class T = void>
struct enable_if : public enable_if_c<Cond::value, T> {};
template <bool B, class T>
struct lazy_enable_if_c {
typedef typename T::type type;
};
template <class T>
struct lazy_enable_if_c<false, T> {};
template <class Cond, class T>
struct lazy_enable_if : public lazy_enable_if_c<Cond::value, T> {};
template <bool B, class T = void>
struct disable_if_c {
typedef T type;
};
template <class T>
struct disable_if_c<true, T> {};
template <class Cond, class T = void>
struct disable_if : public disable_if_c<Cond::value, T> {};
template <bool B, class T>
struct lazy_disable_if_c {
typedef typename T::type type;
};
template <class T>
struct lazy_disable_if_c<true, T> {};
template <class Cond, class T>
struct lazy_disable_if : public lazy_disable_if_c<Cond::value, T> {};
} // namespace lemon
#endif