//
// Copyright (c) 2002 by Stephen C. Dewhurst
// Permission to use, copy, modify, distribute and sell this software for any purpose is
// hereby granted without fee, provided that the above copyright notice appears in all copies
// and that both that copyright notice and this permission notice appear in supporting documentation.
// The author or makes no representations about the suitability of this software for any purpose.
// It is provided "as is" without express or implied warranty.
//

// "typeof" operator implementation
//
// Described in CUJ 20(8, 10, and 12), August, October, and December 2002:  "A Bit-Wise Typeof"
// 
#ifndef UTILS_H
#define UTILS_H

//
//	Some utilities that will prove useful.
//	These are borrowed from Loki.
//
template <bool cond, typename A, typename B>
struct Select {
    enum { result = cond };
    typedef A Result;
};

template <typename A, typename B>
struct Select<false,A,B> {
    enum { result = false };
    typedef B Result;
};

template <int v>
struct Int2Int {
	enum { value = v };
};

//
//	Type qualifier utilities.
//

template <typename T>
struct IsConst {
    enum { result = false }; };

template <typename T>
struct IsConst<const T> {
    enum { result = true }; };

template <typename T>
struct DeConst {
    typedef T R;
};

template <typename T>
struct DeConst<const T> {
   typedef T R;
};

template <typename T>
struct IsVol {
    enum { result = false }; };

template <typename T>
struct IsVol<volatile T> {
    enum { result = true }; };

template <typename T>
struct DeVol {
    typedef T R; };

template <typename T>
struct DeVol<volatile T> {
    typedef T R; };

template <typename T>
struct IsQual {
    enum { result = IsConst<T>::result || IsVol<T>::result }; };

template <typename T>
struct DeQual {
    typedef typename DeVol<typename DeConst<T>::R>::R R; };

#endif