src/tint/utils/symbol/generation_id.h

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#ifndef SRC_TINT_UTILS_SYMBOL_GENERATION_ID_H_
#define SRC_TINT_UTILS_SYMBOL_GENERATION_ID_H_

#include <stdint.h>

#include "src/tint/utils/rtti/traits.h"

namespace tint {

/// A GenerationID is a unique identifier of a generation.
///
/// GenerationID can be used to ensure that objects referenced by the generation are owned
/// exclusively by that generation and have accidentally not leaked from another generation.
class GenerationID {
  public:
    /// Constructor
    GenerationID();

    /// @returns a new globally unique GenerationID
    static GenerationID New();

    /// Equality operator
    /// @param rhs the other GenerationID
    /// @returns true if the GenerationIDs are equal
    bool operator==(const GenerationID& rhs) const { return val == rhs.val; }

    /// @returns true if this GenerationID is valid
    explicit operator bool() const { return val != 0; }

  private:
    explicit GenerationID(uint32_t);

    uint32_t val = 0;
};

}  // namespace tint

#endif  // SRC_TINT_UTILS_SYMBOL_GENERATION_ID_H_