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/// \file engine/action.hpp
/// Representation of user-initiated actions.

#if !defined(ENGINE_ACTION_HPP)
#define ENGINE_ACTION_HPP

#include <ostream>

#include "utils/shared_ptr.hpp"

namespace engine {


class context;


/// Representation of an action.
///
/// The instances of this class are unique (i.e. copying the objects only yields
/// a shallow copy that shares the same internal implementation).  This is a
/// requirement for the 'store' API model.
class action {
    struct impl;

    /// Pointer to the shared internal implementation.
    std::shared_ptr< impl > _pimpl;

public:
    explicit action(const context&);
    ~action(void);

    const context& runtime_context(void) const;

    bool operator==(const action&) const;
    bool operator!=(const action&) const;
};


std::ostream& operator<<(std::ostream&, const action&);


}  // namespace engine

#endif  // !defined(ENGINE_ACTION_HPP)