state_id.h

#ifndef STATE_ID_H
#define STATE_ID_H
 
#include <iostream>
 
// For documentation on classes relevant to storing and working with registered
// states see the file state_registry.h.
 
class StateID {
    friend class StateRegistry;
    friend std::ostream &operator<<(std::ostream &os, StateID id);
    template<typename>
    friend class PerStateInformation;
    template<typename>
    friend class PerStateArray;
    friend class PerStateBitset;
 
    int value;
 
    // No implementation to prevent default construction
    StateID();
 
public:
    ~StateID() {}
 
    // HACK
    explicit StateID(int value_)
        : value(value_)
    {
    }
 
    static const StateID no_state;
 
    bool operator==(const StateID &other) const {
        return value == other.value;
    }
 
    bool operator!=(const StateID &other) const {
        return !(*this == other);
    }
 
    // HACK
    int get_value() const { return value; }
};
 
 
#endif