Enum.h

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/*
 * This file is part of plptools.
 *
 *  Copyright (C) 2000 Henner Zeller <hzeller@to.com>
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  along with this program; if not, see <https://www.gnu.org/licenses/>.
 *
 */
#ifndef _ENUM_H_
#define _ENUM_H_
 
#include "config.h"
 
#include <assert.h>
#include <map>
#include <string>
 
#include "plpintl.h"
 
class EnumBase {
protected:
    class i2sMapper {
    private:
        typedef std::multimap<long, const char*> i2s_map_t;
 
        //typedef map<const char*, long> s2i_map_t;
 
        i2s_map_t stringMap;
    public:
        void add(long, const char*);
 
        std::string lookup(long) const;
 
        long lookup (const char *) const;
 
        bool inRange(long) const;
    };
};
 
template<typename E>
class Enum : private EnumBase {
public:
    struct sdata {
        sdata();
        i2sMapper    stringRep;
        std::string name;
        E           defaultValue;
    };
    static sdata staticData;
 
    E value;
 
public:
    Enum() : value(staticData.defaultValue) {}
 
    Enum(E init) : value(init){
        // if this hits you and you're sure, that the
        // value is right .. is this Enum proper
        // initialized in the Enum<E>::sdata::sdata() ?
        assert(inRange(init));
    }
 
    Enum(const std::string& s) : value(getValueFor(s)) {
        assert(inRange(value));
    }
 
    inline Enum& operator = (E setval) {
        value = setval;
        assert(inRange(setval));
        return *this;
    }
 
    inline Enum& operator = (const Enum& rhs) {
        if (&rhs != this)
            value = rhs.value;
        return *this;
    }
 
    inline operator E () const { return value; }
 
    std::string toString() const { return getStringFor(value); }
 
    operator const char *() const { return toString().c_str(); }
 
    static bool inRange(long i) {
        return (staticData.stringRep.inRange(i));
    }
 
    static std::string getEnumName() { return staticData.name; }
 
    static std::string getStringFor(E e) {
        return staticData.stringRep.lookup((long) e);
    }
 
    static E getValueFor(const std::string &s) {
        return (E) staticData.stringRep.lookup(s.c_str());
    }
};
 
template<typename E> typename Enum<E>::sdata Enum<E>::staticData;
 
#define ENUM_DEFINITION_BEGIN(EnumName, initWith)                             \
                                                                          \
template <> Enum<EnumName>::sdata::sdata() :                                  \
    name(#EnumName),defaultValue(initWith) {
 
#define ENUM_DEFINITION_END(EnumName) \
} template Enum< EnumName >::sdata Enum< EnumName >::staticData;
 
template <typename E>
inline std::ostream& operator << (std::ostream& out, const Enum<E> &e) {
    return out << e.toString().c_str();
}
 
#endif /* _ENUM_H_ */