143 

   143 

   144   const void* identity() const {

   144   const void* identity() const {

   145     return _identity;

   145     return _identity;

   146   }

   146   }

   147 

   147 

   150   void acquire(const void* id);

   148   void acquire(const void* id);

   151   bool try_acquire(const void* id);

   149   bool try_acquire(const void* id);

   152   bool acquired_by(const void* id) const;

   150   bool acquired_by(const void* id) const;

   153   bool acquired_by_self() const;

   151   bool acquired_by_self() const;

   154   void release();

   152   void release();