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28
29/// \file engine/action.hpp
30/// Representation of user-initiated actions.
31
32#if !defined(ENGINE_ACTION_HPP)
33#define ENGINE_ACTION_HPP
34
35#include <ostream>
36
37#include "utils/shared_ptr.hpp"
38
39namespace engine {
40
41
42class context;
43
44
45/// Representation of an action.
46///
47/// The instances of this class are unique (i.e. copying the objects only yields
48/// a shallow copy that shares the same internal implementation).  This is a
49/// requirement for the 'store' API model.
50class action {
51    struct impl;
52
53    /// Pointer to the shared internal implementation.
54    std::shared_ptr< impl > _pimpl;
55
56public:
57    explicit action(const context&);
58    ~action(void);
59
60    const context& runtime_context(void) const;
61
62    bool operator==(const action&) const;
63    bool operator!=(const action&) const;
64};
65
66
67std::ostream& operator<<(std::ostream&, const action&);
68
69
70}  // namespace engine
71
72#endif  // !defined(ENGINE_ACTION_HPP)
73