optional_ref.h

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 *       - Pierre-Henri WUILLEMIN(_at_LIP6)                                 *
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#ifndef GUM_OPTIONAL_REF_H
#define GUM_OPTIONAL_REF_H
 
#include <optional>
 
namespace gum {

  template < typename T >
  class optional_ref {
    T* _ptr_ = nullptr;
 
    public:
    optional_ref() noexcept = default;
 
    optional_ref(std::nullopt_t) noexcept;
 
    optional_ref(T& ref) noexcept;
 
    optional_ref(T&&) = delete;
 
    explicit operator bool() const noexcept;
 
    bool has_value() const noexcept;
 
    T& value() const;
 
    T& operator*() const;
 
    T* operator->() const noexcept;
  };
 
}   // namespace gum
 
#include <agrum/base/core/optional_ref_tpl.h>
 
#endif   // GUM_OPTIONAL_REF_H